Compare · checked 31 October 2026

A PLCSIM alternative for practising Siemens code

Siemens S7-PLCSIM runs your TIA Portal project on a simulated S7 controller on your PC, so you can test it without hardware. It simulates the controller, not the machine. PLC Gym runs your Siemens code in a web browser against a 3D machine that responds, but it isn't TIA Portal. Each is right for a different job.

Try the same task free See the simulator

PLC Gym's 3D process tank, with a mixer, a pump, valves and a control panel — PLC Gym’s own 3D process tank, one of the machines your code runs.

The short answer

Which should you choose?

Choose S7-PLCSIM if

You're testing a real TIA Portal project before it goes to site.
You need your exact controller, firmware and hardware configuration.
You're learning TIA Portal's own menus and online tools.

Choose PLC Gym if

You're learning the logic and don't have TIA Portal or a licence.
You want a machine that reacts, and tests that check every rule.
You're on a Mac, a Chromebook or a PC you can't install software on.

Side by side

What each can and can’t do

S7-PLCSIM facts checked on its own pages on 31 October 2026.
Question	S7-PLCSIM	PLC Gym
What is simulated?	PartlyThe controller. Your TIA Portal project runs on a virtual S7 PLC.	YesThe controller and the machine. Your code drives a 3D process that responds.
Where does it run?	PartlyOn a Windows PC, with TIA Portal. TIA Portal V21 needs 64-bit Windows 10 or 11, or Windows Server, and at least 8 GB of memory.	YesAny modern browser on a laptop, desktop, Mac or Chromebook. A phone is fine for trying the machines and reading lessons.
Your real TIA Portal project	YesYes. It downloads like a real PLC, with the same online and watch tools.	PartlyPartly. Paste or upload an SCL source exported from TIA Portal and run it on a 3D machine. Not the whole project: no hardware configuration, networks or online tools.
A machine to control	NoNo. You set inputs by hand in a watch table, or connect a process model such as Siemens SIMIT to PLCSIM Advanced.	Yes26 working 3D machines, from a pump to a whole factory, run by your code.
Controllers and hardware	YesS7-1200, S7-1500 and ET 200SP, among others. PLCSIM Advanced covers the S7-1500 and ET 200SP families.	NoNo hardware model. No hardware configuration, networks or fieldbus. You write the logic in a function block, with your own blocks and data types.
Lessons and marking	NoNo. It's a test tool.	YesA step-by-step course, 74 missions and 20 challenges. Automatic tests check every one, scan by scan.
Other makers	NoSiemens only.	YesRockwell Studio 5000 languages and Beckhoff TwinCAT Structured Text too.

PLC Gym’s own limits are in the table too. The language reference lists where its simulator differs from TIA Portal and Studio 5000.

See for yourself

Try the same task here

Questions

Common questions

Is PLC Gym a free PLCSIM alternative?

For learning, yes: the free plan includes the first course module in all four Siemens languages it supports. Pro is £15 a month. Everything is free while we test, until 5 December 2026.

Can PLC Gym replace PLCSIM for a real project?

No. To test a real TIA Portal project, with your controller, firmware and hardware configuration, use PLCSIM. PLC Gym is for learning and practising the logic. For a quick look at how a block of your SCL behaves, you can paste it into PLC Gym's code test page and run it on a 3D machine.

Can I take my PLC Gym code into TIA Portal?

Yes. Siemens SCL exports as an external source file (.scl) that TIA Portal can import.

Sources

Where these facts come from

Checked on 31 October 2026. Prices and features change, so check S7-PLCSIM’s own site before you buy.

S7-PLCSIM is a trademark of its owner. PLC Gym is independent and is not affiliated with or endorsed by its makers.