PLC Simulator
Factory IO alternative

A Factory IO Alternative That Runs in Your Browser

Factory I/O is a capable Windows 3D factory tool with external PLC connectivity. Our alternative now adds browser-based 3D composition to its built-in PLC, HMI, grading and fault workflows. Here is the honest boundary.

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This comparison changed: we now have a reusable 3D factory builder too.

The difference is no longer 3D versus 2D. Our 3D Sandbox combines reusable factory composition, built-in PLC tags, failure injection, guided grading and a browser runtime. Factory I/O remains stronger for external vendor-IDE connectivity and its mature Windows desktop ecosystem.

143
reusable components
3
lazy-loadable packs
PLC
driven motion + faults
Build in 3D Sandbox Explore 3D PLC simulation

Public viewer is free. Guided 3D starts on Basic; composing and saving custom 3D scenes is Pro.

Live WebGL component viewer
Drag to orbit · scroll to zoom · choose any componentOpen full viewer ↗

Opening honesty

We make one of the tools being compared.

We have tried to be fair to Factory I/O. It remains the better fit when external Windows vendor-IDE connectivity is the requirement. Ours is the better fit when you want the PLC editor, HMI, reusable 3D factory, generated tags, failure injection and automated training evidence in one browser workspace.

A free no-install browser PLC simulator running in a tab on Mac, Linux, and Chromebook — the cross-platform alternative to the Windows-only Factory IOA web browser window running a PLC ladder logic simulator with an input/output strip, requiring no installation or download.plcsimulator.app/playno installINPUTSOUTPUTS
No Windows VM, no vendor IDE — the whole simulator runs in a browser tab.

Background

What Factory IO actually is

Factory IO is a 3D factory simulator from Real Games, a Portuguese studio that has been building industrial training software since the early 2010s. You drag factory components — conveyors, pushers, pneumatic cylinders, sensors, stackers, arms — into a 3D scene, then connect that scene to a real PLC program running elsewhere (TIA Portal, Studio 5000, Codesys SoftPLC, Do-more Designer) via OPC UA or Modbus TCP.

Factory I/O currently offers subscription and perpetual editions. Its official pages list Starter at €40/year or €109 perpetual and Ultimate at €28/month, €278/year or €765 perpetual. Starter includes the Control I/O FBD softPLC; workflows using TIA Portal, Studio 5000 or another vendor IDE bring that tool and licence separately.

Digital input and output mapping between sensors and actuators and a PLC program — the same scene I/O model Factory IO exposes over OPC UA and Modbus, built directly into this browser alternativeA digital input pushbutton wired to a PLC input card, and a PLC output card driving a lamp, with a sinking versus sourcing hint.I/O CARDINPUTOUTPUTPushbuttonI:0/0LampO:0/0sinking (NPN) vs sourcing (PNP)
Factory IO bridges scene I/O to your PLC over OPC UA or Modbus. We wire the same digital inputs and outputs straight into the editor.

Strengths

What Factory IO does well

3D visualisation

The mature desktop scene and physical interactions are genuinely effective. Watching code drive a spatial line reveals relationships a flat diagram can hide.

Component library

A broad, established parts catalogue covers loads, conveyors, operators, sensors, actuators and stations. You can compose a useful line quickly.

Vendor-IDE integration

The OPC UA / Modbus TCP bridge lets you run your real TIA Portal or Studio 5000 program against the 3D scene. If your day job uses one of those IDEs, Factory IO feels continuous with it.

A start/stop motor control circuit driving a conveyor — the kind of control logic you write against Factory IO's 3D line and grade automatically in this browser-based Factory IO alternativeA 3-wire motor control circuit: Stop and Start pushbuttons, a contactor coil with a seal-in auxiliary contact and an overload contact, driving a motor.StopStartM (seal-in)OLMMmotor
The logic that drives a Factory IO conveyor is the same logic you write and auto-grade here.

Learner pain points

Where Factory IO falls short if you are still learning

Windows-only install

If you are on a Mac, Linux box, Chromebook, or any locked-down work device, Factory IO is a non-starter without a Windows VM and another Windows licence.

Vendor workflows add another tool

Starter includes a Control I/O FBD softPLC. To practise TIA Portal, Studio 5000, Codesys or another vendor workflow, that separate IDE, driver setup and licensing still apply.

Licence cost stacks fast

Ultimate is listed at €28/month, €278/year or €765 perpetual before any separate vendor IDE. That can be entirely reasonable for working engineers, but it is meaningful friction for a beginner.

No built-in curriculum

You get a box of 3D parts, not a scored syllabus. There is no auto-grader telling you whether your program actually solves the scenario — you decide by watching the line run.

Feature comparison

Factory IO vs plcsimulationsoftware.com

FeatureFactory IOOurs
PlatformWindows onlyAny modern browser (Mac, Linux, Chromebook, Windows)
PriceStarter €40/yr; Ultimate €28/mo (official list pricing)Public viewer free; Basic $12/mo; Pro $29/mo
Includes PLC editorStarter: Control I/O FBD; vendor IDEs separateYes — ladder and Structured Text built in
Scored scenariosNo built-in objective graderYes — auto-graded scenario library
DialectsDepends on the IDE you connectIEC 61131-3, Allen-Bradley, Siemens
Install footprint~2 GB + vendor IDE 10–20 GBZero — runs in the browser
VisualisationMature Windows desktop 3D factory2D + additive browser 3D scenarios and custom 3D Sandbox
Interview-timer modeNoYes (Pro)
Portfolio PDF exportNoYes (Pro)
Works on school-issued ChromebookNoYes
The five IEC 61131-3 programming languages with Allen-Bradley and Siemens dialects built in — coverage Factory IO leaves to whichever vendor IDE you connect, included free in this alternativeThe five IEC 61131-3 PLC programming languages as chips: Ladder Diagram, Function Block Diagram, Structured Text, Instruction List and Sequential Function Chart.IEC 61131-3 — five languagesLDLadder DiagramFBDFunction BlockSTStructured TextILInstruction ListSFCSequential Func. Chart
Factory IO depends on whatever IDE you connect. We ship IEC 61131-3 with Allen-Bradley and Siemens dialects in the box.
A Structured Text routine running in the editor — write ST as well as ladder in this free browser Factory IO alternative without installing a vendor PLC IDEA small Structured Text code block in an editor: an IF/THEN condition, a TON timer call and assignments, showing text-based PLC programming.main.st — Structured Text1IF Start AND NOT Stop THEN2 Run := TRUE;3END_IF;4DelayTmr(IN := Run, PT := T#5s);5Lamp := DelayTmr.Q;
Practise Structured Text and ladder side by side — no vendor IDE install required.

Pick Factory IO if…

  • You are on Windows already.
  • You already own TIA Portal, Studio 5000, or Codesys.
  • You want 3D visualisation as a priority.
  • You need its established external PLC and vendor-IDE driver workflow.
  • You are an instructor with a Windows lab and licence budget.

Pick us if…

  • You are on a Mac, Linux machine, or Chromebook.
  • You do not have a TIA Portal or Studio 5000 licence.
  • You want scored feedback, not visual-only feedback.
  • You want to practise IEC, Allen-Bradley, and Siemens dialects side-by-side.
  • You are doing interview prep in the next four weeks.
  • You want a free tier with no credit card.

Try it

Scenarios that cover the same ground as Factory IO demos

The PLC scan cycle — read inputs, execute logic, write outputs — running on a real execution model in this browser Factory IO alternative, not a static puzzleThe repeating PLC scan cycle: read inputs, execute the ladder logic, update outputs, then housekeeping, looping continuously.1Read Inputs2Execute Logic3Update Outputs4HousekeepingSCANCYCLE
Every scenario runs a real read-execute-write scan cycle — the same control model behind a Factory IO scene, scored automatically.

Conveyor Sort

Pushers, sensors, and a diverter — the classic Factory IO "Sorting by Height" feel.

View scenario →

Palletizer

Stack cartons onto a pallet with counting and layer-change logic.

View scenario →

Bottling Line

Fill, cap, and label with station-to-station interlocks and fault handling.

View scenario →

Pick & Place

Two-axis arm with position sensors and grip feedback.

View scenario →

Carton Erector

Timed pneumatic sequence with confirmation sensors.

View scenario →

Case Packer

Sequenced fill-count-release with fault recovery.

View scenario →
A TON on-delay timer sequencing a pneumatic station — the timed actuator logic behind a Factory IO carton-erector scenario, modelled in this browser alternativeA TON on-delay timer: the accumulated time bar ramps up toward the preset value, and the done (DN) bit turns on when the accumulator reaches preset.TONPRE 5000ACCACC ramps to PREPREDNdone bit
Timed pneumatic sequences — like the carton erector — use real TON/TOF timers, not animation tweens.
A seal-in latch holding a motor running after a momentary start — the start/stop interlock pattern you build for every Factory IO conveyor, graded in this Factory IO alternativeA seal-in latch rung: a Start contact in parallel with a Hold contact, in series with a normally-closed Stop contact, driving an output coil.StartHold (seal)StopMotor
Seal-in latching is the first interlock most learners hit — drill it with scored feedback.

Third options

Neither fits? Here is what else to consider.

  • LogixPro 500 — classic Allen-Bradley SLC 500 classroom simulator. Dated but well-known in US colleges. See our LogixPro alternative comparison.
  • Codesys — the industry-reference IEC 61131-3 IDE, free to download, runs its own SoftPLC simulation. Windows-only and demo mode shuts down after 2 hours. See our Codesys alternative comparison.
  • PLC-Fiddle — the lightest possible "try ladder in 30 seconds" browser tool. Ladder-only, no scored scenarios. See our PLC-Fiddle alternative comparison.
  • VirtualPlant — a free, open-source 3D factory simulator that runs on Windows, Linux, and macOS. The closest thing to a free Factory IO clone for the 3D look, though it is a smaller community project with fewer components and you still bring your own PLC program.
  • FluidSIM — Festo's 3D pneumatic and hydraulic circuit simulator with PLC control. Strong if your focus is the fluid-power side of a machine rather than ladder fundamentals.
  • OpenPLC on a Raspberry Pi — if you want real hardware for under $100 and do not mind a serious setup weekend.

Use cases

Can I use this instead of Factory IO for…?

The honest answer depends on what you are trying to get out of the exercise. Both products can now provide 3D composition; the practical split is usually external vendor-IDE connectivity and desktop scene maturity versus an integrated editor, faults and scored execution:

  • Learning ladder, ST, or interlock logic from scratch? Yes — and you get an auto-grader telling you whether it is correct, which Factory IO does not. Start on the scenarios page.
  • School or college coursework on a Chromebook? Yes — Factory IO will not install, and our free tier needs no licence or admin rights.
  • Interview prep in the next few weeks? Yes — use the timed mode and PDF portfolio export; that is exactly what we built it for.
  • Connecting a real vendor IDE to a mature desktop 3D scene? Choose Factory I/O. Its established driver workflow is the better fit for that requirement.
  • A production digital twin or CAD-accurate virtual commissioning model? Neither product should be selected from this comparison alone. Validate CAD import, kinematics, collisions, cycle-time accuracy, vendor interfaces and engineering evidence with a production commissioning specialist.
A fault-finding flow for diagnosing why a scored scenario does not pass — the structured debugging Factory IO leaves you to eyeball, made explicit in this browser PLC simulator alternativeA PLC fault-diagnosis flow from top to bottom: observe the symptom, check the inputs, check the logic, check the outputs, then apply the fix.SymptomCheck inputsCheck logicCheck outputsFix
When a scenario fails, the grader points you at the failing test case — no guessing from a 3D scene whether the line "looked right".

Complementary use

Many learners actually use both

Drill fundamentals with us — scored feedback, any OS, no install — and graduate to Factory IO on a Windows machine when you want the 3D commissioning feel and are already working in TIA Portal or Studio 5000. The two tools answer different questions and do not compete head-on for a serious learner's time.

Cost

The free Factory IO alternative

Searching for a free Factory IO alternative usually means one of two things: you do not want to spend money on software yet, or you need something that works on the device in front of you right now. This simulator covers both. The free tier requires no credit card and includes the complete Beginner Track plus starter curriculum, wiring and fault-finding practice in any modern browser on any OS.

As checked on 22 July 2026, Factory I/O lists Starter at €40/year or €109 perpetual and Ultimate at €28/month, €278/year or €765 perpetual. Starter includes the Control I/O FBD softPLC; a TIA Portal, Studio 5000 or other vendor-IDE workflow uses that separately licensed tool. If you are early in your learning path and want ladder or Structured Text against a simulated machine without installing another product, the free path here is the simpler starting point.

Pricing

Factory I/O pricing (and what the alternative costs)

Factory I/O is paid Windows desktop software licensed per seat, with subscription and perpetual choices plus a free time-limited trial. Real Games can change its editions and prices, so verify the official editions page. Starter includes Control I/O; using TIA Portal, Studio 5000, CODESYS or another vendor IDE is a separate workflow and may carry separate licensing.

The cost structure here is different in kind, not just in size: a free tier with no trial clock, Basic for the wider core curriculum and guided practice, and Pro for every published scenario, the 3D Sandbox and career tools. Because the editor is built in, there is no vendor IDE to license, and because it is delivered in the browser, one account works on every machine you own instead of one licensed seat.

Does Factory I/O run on a Mac? No — Factory I/O is Windows-only, so on macOS it needs a Windows VM and licence on top of the seat price. The browser alternative runs natively on a Mac (Intel or Apple Silicon) in Safari or Chrome.

Questions

Factory IO alternative FAQ

Yes for visual PLC training and custom factory composition, but not identically. Both now provide reusable 3D factory components and PLC-driven motion. Our advantage is one browser workspace with ladder, Structured Text, HMI, generated tags, fault injection and objective grading. Factory I/O remains stronger when you need its external vendor-IDE drivers and Windows desktop ecosystem.

Give it five minutes.

No install. No credit card. Start a conveyor or palletizer scenario right now.

Start free →