Is this PLC simulator free?

Yes. 27 practice records are source-tagged for free-tier access, although visibility can vary by account, entitlement, and staged rollout. A free account requires no credit card and has no trial clock; /try guides visitors through one first program without an account.

Do I need to install anything to use the PLC simulator?

No. The entire PLC simulator runs in the browser. There is no Windows runtime, no JRE, and no vendor license key. Any modern Chrome, Firefox, Safari, or Edge release works — on Windows, macOS, Linux, or Chromebook.

Does the PLC simulator actually execute real ladder logic?

Yes. Your program is parsed into an intermediate representation, scheduled onto a simulated scan cycle, and executed against an IO table that drives the machine model. Supported exercises include contacts, coils, timers, counters, latch/unlatch, edge detection, comparisons, math, and PID. It remains a learning simulator rather than a substitute for validation on the target controller and hardware.

Which PLC brands and dialects does the simulator support?

The learning set contains 9 dialect tracks: IEC 61131-3, Allen-Bradley, Siemens SCL, Mitsubishi, Omron, KEYENCE KV, Schneider Unity, Delta, Instruction List. Vendor-style support teaches transferable syntax and logic patterns; it does not emulate every instruction or firmware behavior of each production runtime.

Can I export my PLC code to a real controller?

You can copy the editor text into another environment, but text portability is not native-project compatibility. Even IEC 61131-3 Structured Text can require changes to types, libraries, task configuration, I/O mapping, persistence, timing, and vendor extensions. Native Siemens and Rockwell project export is not a current capability; validate adapted code in the official target tool and on supervised hardware.

How is this different from PLCSIM, Logix Echo, Logix Emulate, or CODESYS?

Official vendor tools prioritize compatible native projects, controller behavior, and engineering workflows. This simulator prioritizes immediate browser access, auto-graded machine practice, and 9 learning-dialect tracks. Vendor-style tracks are for learning and do not reproduce every instruction, project format, or firmware behavior of a production runtime.

Is PLC design software the same as electrical control-panel design software?

No. PLC design software usually means an editor or simulator used to design, execute, and test control logic. Electrical control-panel design software handles schematics, wire numbers, terminals, devices, enclosure layout, and bills of materials. A real project normally uses both, followed by validation in the official vendor tool and on supervised hardware.

Can I use the PLC simulator on a Chromebook?

Yes. Because the simulator runs entirely in the browser, Chromebooks work as well as any other machine. There is nothing to install and no Android or Linux subsystem required. Open the URL, pick a scenario, and start writing ladder logic.

Is there a mobile or iPad version of the PLC simulator?

The simulator runs in mobile browsers. The code editor is usable on a tablet in landscape mode. On phones the screen width is tight for ladder logic editing, but the simulation canvas and IO table render correctly. A dedicated mobile layout is on the roadmap.

Do I need to install anything?

No. The entire PLC simulator runs in the browser. There is no Windows-only runtime, no JRE, no vendor license key. Any modern Chrome, Firefox, Safari, or Edge release works — on Windows, macOS, Linux, or a Chromebook with zero configuration.

Does it actually execute real ladder logic?

Yes. Your program is parsed into an intermediate representation, scheduled onto a simulated scan cycle, and executed against an IO table that drives the machine model. Supported exercises include contacts, coils, timers, counters, latch/unlatch, edge detection, comparisons, math, and PID. It remains a learning simulator rather than a substitute for validation on the target controller and hardware.

Which PLC brands and dialects does the simulator support?

The learning set contains 9 dialect tracks: IEC 61131-3, Allen-Bradley, Siemens SCL, Mitsubishi, Omron, KEYENCE KV, Schneider Unity, Delta, Instruction List. Vendor-style tracks teach transferable syntax and logic patterns; they do not emulate every instruction or firmware behavior of each production runtime.

Can I export my code to a real PLC?

You can copy the editor text into another environment, but text portability is not native-project compatibility. Even IEC 61131-3 Structured Text can require changes to types, libraries, task configuration, I/O mapping, persistence, timing, and vendor extensions. Native Siemens and Rockwell project export is not a current capability; validate adapted code in the official target tool and on supervised hardware.

How is this different from PLCSIM, Logix Echo, Logix Emulate, or CODESYS?

Official vendor tools prioritize compatible native projects, controller behavior, and engineering workflows. This simulator prioritizes immediate browser access, auto-graded machine practice, and 9 learning-dialect tracks. Vendor-style tracks are for learning and do not reproduce every instruction, project format, or firmware behavior of a production runtime.

Is PLC design software the same as electrical control-panel design software?

No. PLC design software usually means an editor or simulator used to design, execute, and test control logic. Electrical control-panel design software handles schematics, wire numbers, terminals, devices, enclosure layout, and bills of materials. A real project normally uses both, followed by validation in the official vendor tool and on supervised hardware.

Can I use the PLC simulator on a Chromebook?

Yes. Because the simulator runs entirely in the browser, a Chromebook works as well as any Windows or Mac machine. There is nothing to install, no Android subsystem required, no Linux beta needed. Open the URL, pick a scenario, and start writing ladder logic.

Is there a mobile or iPad version?

The simulator runs in mobile browsers today. The code editor is usable on a tablet in landscape mode. On phones the screen width is tight for ladder-logic rung editing, but the simulation canvas and IO table render correctly. A dedicated mobile layout is on the roadmap.

PLC Simulator

Free Tier Available

PLC Simulator & Programming Software — Run Online

Q: Can I practice PLC programming without hardware?

Yes. The source catalog defines 140 practice records, with availability varying by account state, tier, entitlement, and staged rollout. Browser simulation develops logic skills; wiring and commissioning still require supervised work with suitable equipment.

Practice across 9 learning dialect tracks, press Run, and watch a simulated machine respond in real time. The catalog defines 140 published practice records, with access varying by plan and rollout. No install, no license key.

Start Free →Try without an account

Real PLC programming software footage

See this exact skill in the working simulator.

Watch the real browser product respond to the task on this page, then try the same practical workflow yourself. No slides, concept mockups, install, or credit card.

Try this in the browser

PLC Programming Software — Browser Simulator Product Walkthrough

This is a live PLC simulator running in your browser right now — no plugin, no install.

What it is

What is a PLC Simulator?

A PLC simulator is software that emulates a programmable logic controller so you can write and test PLC code without owning hardware. Instead of wiring up a real rack, connecting IO modules, and commissioning a physical plant, you describe the control logic in ladder rungs or structured text, press Run, and a software model of the machine responds — tanks fill, motors spin, conveyors move, alarms trigger. Every instruction executes against a real scan cycle: read inputs, execute program, write outputs. The difference from a real PLC is that the IO table is virtual, not wired.

What makes a browser-based PLC simulator different is the absence of install friction. Traditional PLC simulation software — such as Siemens S7-PLCSIM, Rockwell FactoryTalk Logix Echo, Studio 5000 Logix Emulate, and CODESYS Simulation mode — works inside an installed engineering environment, with operating-system, version, compatibility, and licensing conditions that vary by product. That workflow is appropriate for target-project validation, but it adds first-hour friction for a student or engineer on a Chromebook, Mac, Linux computer, or locked-down workstation. A PLC simulator online changes the starting point: load a URL, open the guided exercise, and write a first rung without installing the vendor environment. The result still has to move into the official tool when target fidelity matters.

Not every browser PLC emulator is the same, though. Rung drawing tools let you sketch a ladder diagram but do not actually execute the logic. A genuine plc emulator runs a scan cycle, maintains an IO table, evaluates every rung in order, and updates output coils accordingly. Ours goes further: each scenario ships with a scripted test harness that evaluates your program against specific objectives — correct sequencing, interlock behaviour, timing windows — and returns pass/fail results with failure reasons. That is the difference between drawing a ladder and proving your ladder works. See the full library at /scenarios or jump straight to the PLC programming simulator overview.

A PLC simulator runs entirely in the browser — write logic, press Run, watch the machine respond.

What the simulator teaches

Connect the rung, scan cycle and machine result

A useful PLC simulator does more than draw symbols. It lets you trace a decision from field input through executable logic to an observable machine state, then diagnose the exact layer that failed.

Browser PLC simulator workflow showing a program pane, live input and output indicators, and a running motor control training rig — 01The core loop is visible in one place: edit the program, inspect live I/O and verify the machine outcome instead of guessing from code alone.

PLC scan cycle diagram showing photoeye and pushbutton inputs, program execution, motor and stack-light outputs, and the repeating cycle — 02A simulator must preserve scan order: sample inputs, execute the program, update outputs and repeat. That timing model explains many real ladder-logic mistakes.

Accurate motor seal-in ladder circuit with stop normally closed, start normally open, motor auxiliary contact, motor coil, contactor and overload — 03The classic seal-in lesson connects an accurate ladder pattern to the pushbuttons, contactor auxiliary contact, overload and motor it represents.

PLC troubleshooting lesson tracing a conveyor start failure from emergency stop through input, ladder logic, output and motor load — 04Good simulation teaches diagnosis as an evidence chain—field condition, PLC input, logic state, output command and load—not random part replacement.

PLC programming comparison showing ladder logic, Structured Text and address notation producing the same motor control outcome — 05Syntax and addresses vary, but permissives, state, timing and output behaviour transfer. The shared outcome is the skill worth learning first.

Industrial PLC simulation lab with conveyor sorting, tank filling and robotic pick-and-place stations controlled from a laptop — 06Machine contexts expose different failure modes: sensor sequencing on conveyors, analog state on process skids and interlocks on motion cells.

How it works

How PLC Simulation Works

Every scenario follows the same three-step loop. The whole thing runs in one browser tab — no second window, no separate runtime process.

Write your ladder logic

The Monaco-based editor provides 9 learning dialect tracks: IEC 61131-3, Allen-Bradley, Siemens SCL, Mitsubishi, Omron, KEYENCE KV, Schneider Unity, Delta, Instruction List. Supported exercises cover practical contacts and coils, timers, counters, edge detection, data movement, math, and PID patterns. Vendor-style tracks teach transferable syntax; they do not emulate every instruction or firmware behavior of a production runtime.

Run the simulator

Press Run and the scan cycle starts. Each cycle reads the input image table, executes your rungs top-to-bottom, then writes coil states to the output image. The IO table panel shows every address — %I0.0, %Q0.1, T4:0.ACC — updating live so you can watch a rung evaluate in real time. Set a breakpoint on any rung, or inject a manual input override to test an edge case without waiting for the physics model to reach it.

Watch the machine respond

The Phaser-rendered physics canvas updates as your outputs change. Tanks fill or drain based on valve coil states. Motors spin when the run coil is energised. Conveyors move, lamps light, alarms trigger. Auto-graded test cases evaluate whether the machine hit every objective — correct fill sequence, interlock respected, timing within spec — and return pass/fail with the exact failure reason so you know which rung to fix.

Every scenario in the PLC simulator runs this scan cycle, just like physical hardware.

Design before deployment

PLC Design Software: Build and Prove the Control Logic

PLC design software is usually the programming and simulation environment used to turn a machine requirement into executable control logic. The design work is broader than drawing one ladder rung: define operating states, assign an I/O contract, establish permissives and interlocks, implement the sequence, inject abnormal conditions, and record evidence that the outputs remain safe and deterministic. In this browser simulator, the design loop is edit, run, observe, test, and revise. The machine model makes the result visible while the I/O table and scripted checks expose which assumption failed.

That meaning must not be confused with electrical control-panel design. Electrical CAD and ECAD tools create schematics, wire numbers, terminal plans, device tags, cable schedules, enclosure layouts, and bills of materials. PLC programming tools create controller configuration, tags, routines, function blocks, data structures, and executable logic. The two models meet at the I/O list: every field device and terminal shown on the electrical drawings needs a corresponding controller channel and software tag. A simulator can prove the logic side, but it cannot prove conductor sizing, protective-device coordination, segregation, grounding, field wiring, safety performance, or the exact behavior of target hardware and firmware.

Design surface	Primary artifact	What simulation can prove	What still needs another tool or test
PLC logic design	Tags, routines, state logic, timers, counters, alarms, interlocks	Sequence, scan-order effects, boundary cases, simulated machine response	Exact vendor instructions, firmware, communications, safety and hardware behavior
Electrical panel design	Schematics, terminals, conductors, devices, enclosure layout, BOM	Only the exported I/O contract can be exercised by a PLC simulator	Ratings, protection, heat, clearances, standards compliance and physical inspection
Vendor engineering software	CPU and module configuration, native project, network and diagnostic setup	Vendor emulator can check target-specific code and configured virtual hardware	Final supervised commissioning on the specified controller, I/O and machine

A practical PLC logic-design workflow

Write the requirement as observable behavior. Define start conditions, normal sequence, stop behavior, reset rules, time limits, alarm response, and the safe state.
Freeze the I/O contract. Give every input and output a stable address, tag, signal meaning, normal state, and simulated fault state before coding.
Separate mode, state, command, and feedback. An output command is not proof that a motor, valve, or cylinder moved; feedback must close that evidence gap.
Implement the smallest safe sequence. Add permissives and interlocks first, then timing, retries, alarms, recovery, and operator messages.
Test normal and abnormal paths. Exercise stuck sensors, late feedback, contradictory inputs, rapid button changes, restart after interruption, and boundary timer values.
Port and revalidate. Move the proven pattern into the official vendor project, resolve dialect differences, rerun target-emulator tests, and commission on supervised hardware under the project safety procedure.

Start the design with a testable I/O contract

A useful I/O list describes meaning and evidence, not only an address. This compact conveyor example separates operator requests, safety-derived permissives, field feedback, commands, and alarms so the simulation cannot mistake a commanded output for a proven machine state.

Tag	Direction	Normal meaning	Fault to simulate	Expected response
StartPB	Input	Momentary start request	Chatter for three scans	One accepted request; no duplicate start
StopHealthy	Input	TRUE while stop chain permits motion	Drops during run	Command removed and restart latched out
GuardPermissive	Input	Safety system permits standard control	FALSE before or during start	Start inhibited or run command removed
MotorAux	Input	Contactor feedback proves energisation	Never follows command	Feedback timeout and alarm
ProductPE	Input	Product occupies photoeye	Stuck TRUE	Sequence times out; counter cannot free-run
MotorCmd	Output	Request to energise motor starter	Feedback late or absent	Drop command according to fault policy
RunLamp	Output	Normal automatic run is proven	Command on, feedback off	Lamp remains off
MotorFailAlarm	Output	Command/feedback mismatch exceeded limit	Power-cycle with fault present	Alarm state follows documented retention rule

Acceptance tests turn the design into evidence

Each requirement needs an initial state, an action, an observable result, and a time boundary. “The conveyor works” is not a test; “MotorAux becomes true within 800 ms of MotorCmd or the command drops and MotorFailAlarm latches” is testable in a simulator and later repeatable in the vendor emulator.

Test	Stimulus	Pass evidence	Common design defect exposed
T01 normal start	All permissives true; pulse StartPB	MotorCmd on, MotorAux proven, RunLamp on	Missing seal-in or mode gate
T02 start inhibited	GuardPermissive false; pulse StartPB	MotorCmd remains off	Permissive checked only after start
T03 stop during run	Drop StopHealthy	MotorCmd and RunLamp off in the defined response	Stop omitted from maintained path
T04 missing feedback	Hold MotorAux false after command	Timeout, command policy and alarm all match spec	Timer reset or command/feedback confusion
T05 late feedback boundary	Assert MotorAux just before and just after limit	Deterministic pass/fail at documented threshold	Scan-time boundary ambiguity
T06 chattering start	Toggle StartPB each scan	One state transition; no repeated counters or timers	No edge detection
T07 stuck photoeye	Hold ProductPE true through sequence	Timeout without repeated product count	Level used where an edge was required
T08 restart after interruption	Interrupt run, restore inputs without new start	Restart follows documented manual/automatic rule	Unsafe implicit restart

Know what each verification stage can claim

Passing browser tests is useful design evidence, not a production release certificate. Promote the same tests through increasingly faithful environments and keep the result, software version, assumptions, and unresolved exceptions with the project.

Stage	Useful claim	Evidence to retain	Claim you must not make yet
Browser logic simulation	Algorithm and simulated sequence satisfy defined cases	Logic revision, I/O contract, test inputs, observed outputs	Exact target runtime or hardware is validated
Official vendor emulator	Native project compiles and target-specific simulated behavior passes	IDE/runtime version, CPU target, compile log, trace and test report	Real I/O timing, wiring and machine dynamics are proven
Hardware-in-the-loop or bench	Selected controller and representative I/O respond as tested	Firmware, module revisions, wiring record, measurements and exceptions	The complete installed machine is commissioned
Supervised commissioning	Installed system passes the approved site procedure	Signed results, backups, as-built versions, alarm and safety records	Unreviewed future changes remain covered

Scenarios

140 source-catalogued practice records

Each scenario is a full machine model with an IO list, a written objective, and a scripted test suite. They are ordered by difficulty so you build on each concept before the next one introduces a new instruction or control pattern. Browse the full library at /scenarios. Catalog play requires an account, and availability varies by plan, entitlement, and staged rollout. To begin without an account, use the guided first program.

Traffic Light

Free

Four-way signal with timer chain and all-red safety interlock phase.

Motor Start / Stop

Free

Three-wire control with seal-in, E-stop, and thermal overload interlock.

Conveyor Sort

Pro

Photo-eye sort station with part counters and reject actuator output.

Tank Fill Station

Pro

Level sensors with hysteresis control and latched high-level alarm.

Elevator Controller

Pro

Multi-floor call queue, door timing, and direction logic sequencer.

Batch Mixer

Pro

Multi-step sequencer with ingredient timing and agitator interlock.

Boiler Startup

Pro

Burner management sequence with purge cycle, flame detection, and lockout.

Palletizer

Pro

Layer-building logic with row count, column indexing, and stack reset.

Showing 8 examples from 140 source-catalogued practice records. Browse the catalog →

Reproducible product proof

What the Browser PLC Simulator Actually Proves

This is the public evaluation protocol behind the capability claims on this page. It was published on 31 August 2026 so a reader can repeat the same actions rather than accepting a feature checklist on trust. The current machine-readable product record is facts version 2026-08-09.1, reviewed 2026-08-09. A protocol publication date is not a claim that every browser, entitlement, scenario, vendor version, or physical target was freshly certified on that day.

Each row separates four things that marketing pages often collapse: the claim, the action used to challenge it, the evidence a person should observe, and the boundary that the result cannot cross. That distinction matters for industrial software. A deterministic motor exercise can prove that the learner handled a seal-in and feedback timeout in the declared model. It cannot prove wiring, contactor performance, exact CPU scan timing, network behavior, firmware compatibility, or a machine safety function.

PLC Simulation Software builds and publishes this simulator and this evaluation. It is not Siemens, Rockwell Automation, CODESYS, Mitsubishi Electric, Omron, KEYENCE, Schneider Electric, Delta, or an affiliate or endorsed training provider for those manufacturers. Named vendor-style tracks are scoped learning subsets for transferable syntax and control patterns; they are not the manufacturers' native project formats or complete runtimes.

ID and claim	Action	Observable evidence	Acceptance rule	Important boundary
P01The guided first program opens without an account	Open /try in a private browser session and do not authenticate.	The guided editor, program instructions and machine surface appear before any account gate.	A visitor can begin the guided proof; catalog play may still require an account.	This proves anonymous access to /try, not anonymous access to every catalog scenario.
P02A valid partial program can run	Enter a syntactically valid subset of the requested logic and press Run.	The current valid program executes while incomplete-objective feedback remains visible.	Warnings or incomplete objectives do not silently replace the program with a finished answer.	Invalid syntax and unsupported constructs may still prevent execution.
P03The learning model follows a deterministic scan	Change one simulated input and follow its effect through the program and machine.	The observable order is input sampling, top-to-bottom execution, output update, then deterministic machine advance.	The same starting state, input sequence and valid program produce the same simulated outcome.	Browser scheduling is not a guarantee of a physical controller task period or I/O update time.
P04Stateful seal-in logic persists and releases	Pulse Start, release it, then operate the defined Stop or permissive input.	The motor command persists through the auxiliary logic and clears on the defined release condition.	The state survives Start release but cannot bypass the Stop/permissive path.	The exercise is not a safety-function validation and must not replace a safety-rated circuit.
P05Timers, counters and edge instructions expose state	Run the matching lesson with boundary values and repeated input transitions.	Preset, accumulated/state and done/output behavior can be inspected in the exercise.	The result matches the documented learning semantics and the scenario checks.	Exact vendor firmware, overflow, retentive and time-base behavior must be checked in the target documentation.
P06A wrong program produces diagnostic evidence	Deliberately omit a required interlock or feedback condition, then submit the scenario.	At least one check fails with a reason tied to the missing observed behavior.	The learner sees which required outcome failed rather than only a single opaque score.	A scenario suite proves only its declared checks; it is not exhaustive formal verification.
P07Anonymous and catalog access boundaries are disclosed	Compare /try with a scenario launched from /scenarios while signed out.	The guided first program remains anonymous while catalog play presents the documented account boundary.	The interface does not describe the entire indexed scenario library as anonymously playable.	Scenario visibility can vary by plan, entitlement and staged rollout.
P08Nine learning-dialect tracks have a documented scope	Review the dialect capability document and open representative lessons.	The learning set identifies the dialect tracks and distinguishes shared patterns from target-specific fidelity.	Vendor-style teaching is not presented as complete firmware or project-format emulation.	Supported learning syntax is a subset; production compatibility requires the official vendor environment.
P09Program output changes an observable machine result	Run a valid program, toggle a defined input and compare the output table with the machine state.	Output state and visible equipment behavior change together according to the scenario contract.	Success requires observed behavior rather than the presence of expected source text alone.	The machine is a deterministic teaching model, not a calibrated physical-process digital twin.
P10Portability limits are stated before export	Review the capability, dialect and limitation documents before moving code to another IDE.	Text reuse is distinguished from native project, hardware configuration and validated deployment.	No native Siemens or Rockwell project export is promised as a current capability.	Even portable IEC Structured Text can require type, library, task and vendor-extension changes.
P11Native project and firmware fidelity are excluded	Compare the public limitations with the requirements for a named target CPU and firmware revision.	The page directs exact project, instruction, communication and firmware validation to the official tool.	A browser pass is never described as target-controller acceptance.	Safety, motion, communications and unusual instruction edge cases require target-specific tests.
P12Device and entitlement caveats remain visible	Review mobile, browser, free-tier and catalog statements alongside product-facts.json.	Claims name the no-account route, account boundary and access variability instead of implying universal access.	The public page and machine-readable fact record describe the same material boundary.	Browser/device support and entitled content can change; the dated fact version is the review anchor.

Capability and fact evidence

The capability document and machine-readable fact record define the public counts, access model and learning boundaries used on this page.

Capability matrix Product facts JSON

Instruction and dialect scope

The instruction and dialect records state which learning behavior is represented and where a vendor-specific tool remains authoritative.

Supported instructions Dialect compatibility

Method and known limits

The test-harness method explains scenario checks; the limitation and change records keep exceptions and revisions visible.

Test-harness method Known limitations Changelog

The downloadable public fixture is also available as the capability matrix CSV. When a page claim and a fixture disagree, treat the narrower claim as controlling, record the discrepancy, and use the dated changelog rather than assuming the most favorable interpretation.

Comparison

Compare PLC Programming Software by Learning Goal

The best PLC programming software depends on whether you need browser practice, a vendor engineering workflow, native project files or hardware-faithful emulation. This comparison keeps those jobs separate and notes where installed vendor tools are stronger.

Choose browser-first practice when you need to:

start without installing an IDE or controller runtime;
compare transferable patterns across several learning dialects;
repeat graded machine scenarios with immediate evidence.

Choose the official vendor tool when you need to:

validate exact hardware, firmware and instruction behavior;
test vendor communications, safety or advanced libraries;
commission, download or maintain a production controller.

Use both for a lower-friction workflow:

prototype scan-cycle logic and edge cases in the browser;
port the proven pattern into the target vendor project;
finish validation in the official emulator and on supervised hardware.

Approach or tool	Best fit	Start in browser	Project/runtime fidelity	Built-in graded machine practice	Important boundary	Primary evidence
PLC Simulation Software browser simulator	First-hour ladder/ST practice, graded machine exercises and transferable troubleshooting patterns.	Yes; /try has a no-account guided program.	Learning semantics and deterministic scenario models; no native vendor project or firmware claim.	Yes, for declared scenario checks.	Not a production controller, safety validator or hardware commissioning substitute.	Public capability matrix
Siemens S7-PLCSIM / S7-PLCSIM Advanced	Testing compatible SIMATIC projects, controller instances and Siemens engineering workflows.	No; used with the supported installed Siemens engineering environment.	Higher Siemens project and controller fidelity within the documented product/version scope.	No built-in machine-practice curriculum claimed here.	Confirm supported CPUs, communications and differences from physical hardware in the current manual.	Siemens S7-PLCSIM documentation
Rockwell FactoryTalk Logix Echo	Emulating compatible modern Logix controllers and native projects for virtual testing and automation.	No; installed FactoryTalk/Studio 5000 workflow.	Native Logix-project and controller emulation within the published compatibility matrix.	No built-in graded learning curriculum claimed here.	It emulates controller behavior; it does not turn a virtual pass into physical machine acceptance.	Rockwell Logix Echo product page
Studio 5000 Logix Emulate	Selected legacy or supported Logix application tests where that emulator matches the project environment.	No; Windows engineering workstation workflow.	Logix emulation within documented controller, version and instruction limits.	No built-in graded learning curriculum claimed here.	Rockwell documents behavior and performance differences from physical controllers; verify the exact release.	Rockwell Logix Emulate guide
CODESYS Simulation mode	Running and debugging an IEC application on a simulated target before connecting a physical device.	No; used inside the installed CODESYS Development System.	Application-level simulation governed by the selected device description and documented simulation behavior.	No built-in graded machine-practice curriculum claimed here.	CODESYS explicitly documents simulation differences; physical device and I/O behavior still need validation.	CODESYS simulation-mode help
3D machine or digital-twin simulator	Visual process interaction, material flow and virtual commissioning around a controller or emulator.	Varies by product and deployment.	Potentially richer plant behavior, depending on the model, interfaces and validation evidence.	Varies; many tools require the teacher or engineer to define the task and acceptance logic.	A 3D model still needs a controller connection, trustworthy process parameters and project-specific tests.	3D PLC simulator selection guide

Use one owner for each search task

This /plc-simulator page owns the broad product, capability and best-fit question. The online PLC simulator page owns no-install browser mechanics; the free PLC simulator page owns free-account and access details; and the PLC programming simulator page owns the editing and instruction workflow. Vendor-specific pages cover vendor-style learning, while official vendor products remain the authority for native projects, supported controllers, firmware and production validation. Keeping these jobs distinct gives a visitor a precise next step without manufacturing four near-duplicate answers to the same head term.

Comparison reviewed 31 August 2026 against the linked primary documentation. Availability, licensing, compatibility and product names can change; verify the current release and target matrix before purchase or project commitment. The absence of a graded curriculum claim means none was relied upon for this comparison, not that a vendor or third party can never provide training.

Primary-source reading list

Check PLC programming software claims against primary sources

The comparison above describes different learning and engineering jobs, not interchangeable products. Use the current IEC, CODESYS, Siemens and Rockwell documentation below to confirm target support, simulation limits and instruction behavior before selecting a production workflow.

Audience

Who Uses This PLC Simulator?

Three groups make up most of the active users. Each one has a different reason to avoid the install friction of traditional plc simulation software.

Students and trainees

Mechatronics, electrical engineering, and automation students who need ladder logic practice outside the lab. Most cannot afford per-seat desktop licenses, and university lab machines frequently have admin-locked software installs. A free plc simulator that runs in a browser removes both barriers. The structured scenario library — from basic motor start/stop through PID control and multi-step batch sequencers — maps closely to the control-systems curriculum in technical colleges and universities.

Learn PLC programming →

Plant and controls engineers

Engineers preparing for a controls role interview, or verifying a logic change before a commissioning window. You know the problem: spinning up a Siemens VM or a Rockwell emulator to test three rungs is a 45-minute setup tax, not a five-minute sanity check. A browser PLC emulator lets you draft and test the core logic at a coffee shop, hand it to a colleague for review, and only fire up the full vendor tool when the logic is already known-good. The PLC programming simulator supports practical instruction families for browser-based learning. Vendor-style tracks do not reproduce every instruction or firmware behavior of production runtimes.

Hobbyists and self-learners

People who build home automation projects, tinker with Arduino/Raspberry Pi, and want to understand industrial control logic without buying a starter PLC kit. The guided first program works without an account; catalog practice uses a free account, with access varying by entitlement and rollout. The ladder logic simulator page explains the rung-by-rung mechanics if you are coming from general programming rather than industrial controls.

Ladder logic reference

Ladder Logic in the PLC Simulator

Ladder logic — formally ladder diagram (LD) in the IEC 61131-3 standard — is the most widely used PLC programming language because it reads like the relay circuits PLCs replaced. A program is a stack of horizontal rungs drawn between two vertical power rails. Each rung holds input contacts on the left and one or more output coils on the right. Power is evaluated left to right: when a complete path of true contacts connects the left rail to a coil, that coil energises. Contacts in series form an AND; contacts in parallel form an OR. The PLC simulator evaluates every rung top to bottom, once per scan cycle, exactly like real hardware. For the full symbol set, see the ladder logic symbols reference.

A worked example: motor start/stop with seal-in

The canonical first program is a motor starter. A Start push-button (normally-open, XIC) energises a Motor coil; a Stop push-button (normally-closed, XIO) breaks the rung; and a Motor contact in parallel with Start “seals in” the rung so the motor keeps running after Start is released:

|--[ Start ]--+--[/ Stop ]--( Motor )--|
|             |
|--[ Motor ]--+

Press Run in the simulator and the scan cycle reads the inputs, solves the rung, and writes the Motor coil — you watch the motor spin on the physics canvas and the seal-in hold it on. Tap Stop and the normally-closed contact opens, the path breaks, and the motor stops. This single rung demonstrates contacts, a coil, an OR branch, and latching — the foundation of almost every PLC program. Dozens more worked examples live in the scenario library, each auto-graded against test cases.

The seal-in rung above, drawn as a ladder diagram the PLC simulator executes.

The ladder symbol set used across every PLC simulator scenario.

Supported instruction set

The editor implements the practical instruction families listed below for guided learning, with syntax and naming varying by dialect. Vendor-style tracks do not guarantee every instruction or firmware behavior of a production runtime:

Instruction	Type	What it does
XIC	Contact	Examine If Closed — passes power when the bit is TRUE (normally-open contact).
XIO	Contact	Examine If Open — passes power when the bit is FALSE (normally-closed contact).
OTE	Coil	Output Energise — the coil follows the rung: true when the rung is true.
OTL / OTU	Coil	Output Latch / Unlatch — set a bit and hold it, then reset it on a separate rung.
TON / TOF / TP	Timer	On-delay, off-delay and pulse timers with preset (PT/PRE) and elapsed (ET/ACC).
RTO	Timer	Retentive on-delay — accumulates run-time across cycles; cleared with RES.
CTU / CTD	Counter	Count up / count down on each false-to-true transition; DN at the preset.
R_TRIG / F_TRIG	Edge	Rising- and falling-edge one-shots — fire for a single scan on a transition.
MOV	Data	Move a value or tag into another tag.
ADD / SUB / MUL / DIV	Math	Integer and real arithmetic on tags and constants.
GRT / LES / EQU	Compare	Greater-than, less-than and equal comparisons that gate a rung.
PID	Process	Closed-loop PID control of an analog process value against a setpoint.

TON / TOF / TP timers run on the scan cycle.

CTU / CTD counters increment on rising edges.

9 learning dialect tracks share one browser-based practice environment.

Prefer text? Copy the Structured Text as a starting point, then adapt types, libraries, tasks and I/O for the target CODESYS or OpenPLC project.

Deep-dive guides cover each family in detail: PLC timers, PLC counters, structured text, and the ladder logic symbol reference. Prefer the Allen-Bradley dialect? Start with the Allen-Bradley simulator; for Siemens, the Siemens simulator.

No hardware needed

Can I practice PLC programming without hardware?

Yes. A browser-based PLC simulator can replace the training rack for the logic half of the skill. The source catalog defines 140 published practice records with scripted test cases, although availability varies by account, plan, entitlement, and staged rollout. The exercises execute IEC 61131-3-style logic on a real scan cycle, with nothing to install.

The skill also feeds a growing maintenance job market. The U.S. Bureau of Labor Statistics projects 13% employment growth from 2024 to 2034 and about 54,200 openings each year across industrial machinery mechanics, maintenance workers and millwrights. That occupational outlook is evidence of demand for the wider maintenance field; it does not guarantee a PLC-specific role, wage or hiring outcome.

“Video courses let you nod along; a graded scenario calls your bluff. The moment a scripted test case fails your rung is the moment you actually learn how the scan cycle works — and it is worth more than an hour of watching someone else’s ladder.”
— Paul, builder of this simulator

FAQ

Common questions about the PLC simulator.

Yes. The free account has no credit-card requirement and no expiry. It includes 6 core lessons per supported dialect. The source catalog marks 27 practice records for free-tier access, but what is visible can vary by account, entitlement, and staged rollout. /try is one guided first program that works without an account.

Start Writing PLC Code Free

A free account includes 6 core lessons per supported dialect with no credit card or expiry — or open the guided first program right now without an account.

Start Free →Browse the scenario catalog