The free PLC simulator that runs inside your IDE
Test IEC 61131-3 logic without hardware. The Simulator is built into OpenPLC Editor and Autonomy Edge, with a live debugger and real-time variable graphs. No PLC, no server, nothing extra to set up.
What is the OpenPLC Simulator?
The Simulator is built into OpenPLC Editor, the free and open source IEC 61131-3 IDE, and into the web editor in Autonomy Edge. It runs your control logic entirely on your machine: no PLC to buy, no server to configure, nothing extra to install.
Write your program in Structured Text, Ladder Diagram, Function Block Diagram or Instruction List and click Start Simulator: wires light up green as power flows, the Debugger streams live variable values, and time-series graphs track trends in real time.
That makes the Simulator a practical tool for students learning ladder logic without hardware, and for engineers validating control logic before deploying it. It ships as part of our free PLC programming software, and the same editor deploys your finished program to a real OpenPLC runtime.
What you can simulate
Everything the compiler accepts runs in the Simulator, with full visibility into what your logic is doing.
IEC 61131-3 languages
Simulate Structured Text, Ladder Diagram, Function Block Diagram and Instruction List.
Live execution colouring
Wires turn green as power flows, so you see exactly which paths are active.
Real-time debugger
Variable values update live in the Debugger panel while the simulation runs.
Variable graphs
Plot variables as time series and watch trends unfold in real time.
C and C++ function blocks
Custom function blocks written in C or C++ run right in the Simulator.
Runs in the editor or in your browser
The Simulator runs locally in the desktop editor or in Autonomy Edge in your browser: no hardware, no server, no setup.
How it works
- 1
Download OpenPLC Editor
Grab the free installer for Windows, macOS, or Linux from the download page.
- 2
Write your logic
Build your program in Structured Text, Ladder Diagram, Function Block Diagram, or Instruction List, or add Python and C++ function blocks.
- 3
Click Start Simulator
Watch wires light up green, follow variable values in the Debugger, and graph them over time, all without leaving the editor.
Frequently asked questions
Everything you need to know about simulating PLC logic with OpenPLC.
Test your PLC logic today, no hardware required
Download OpenPLC Editor for Windows, macOS, or Linux and start simulating in minutes.
Download OpenPLC Editor