Program, simulate, and test PLC logic directly in your browser
Visual PLC Studio is an online PLC programming environment. Write ladder logic or Structured Text, run it on a real scan cycle, connect it to a 3D simulator, and bridge to Modbus and OPC UA hardware, with no vendor software or trainer rack required.
What is Visual PLC Studio?
Visual PLC Studio is a browser-based development environment for programmable logic controllers (PLCs). It supports two IEC 61131-3 languages, graphical Ladder Diagram and textual Structured Text, which are kept in sync so you can switch between them. Support for additional languages will be added in the near future. Your program runs on a real scan cycle with a %I/%Q/%M input, output and memory image, so you can watch rungs energize and force inputs and outputs while it runs. It is built for students, instructors, automation engineers and integrators. It is not a safety-rated controller, so use it for learning, prototyping and simulation, never to control real equipment.
Everything you need to learn and prototype PLC control
Four integrated modules cover the whole loop, from writing logic to watching it drive a machine.
Logic Studio
Edit ladder logic rung by rung, or switch to Structured Text. Both are IEC 61131-3 languages engineers use on real controllers, with Function Block Diagram and Sequential Function Chart coming in the near future. Contacts, coils, timers, and counters are all available from the instruction palette.
A real scan cycle, in your browser
Programs are compiled to WebAssembly and executed by a scan engine running in a Web Worker, with an %I / %Q / %M memory map just like a hardware PLC. Watch power flow through each rung live, force inputs and outputs from the force table, and step through behaviour without installing anything.
3D I/O simulation
Bind tags to a 3D scene of buttons, sensors, lamps and cylinders, or connect to an external 3D simulator over Modbus TCP. Test a conveyor or a pick-and-place sequence against a virtual plant before you ever touch a real machine.
Hardware Gateway
A small local agent bridges the browser to the outside world. It exposes your running program as a Modbus TCP server and an OPC UA server, polls Modbus TCP devices, and talks Modbus RTU to USB-serial hardware, with a live packet feed and telemetry charts for debugging.
Tag Scope Database
Declare global and program-scoped tags, build structured data types, and see every address in one place. Tags are the single source of truth shared by your logic, your simulation bindings and your gateway mappings.
Open project format
Projects are stored as IEC 61131-10 (PLCopen XML), the vendor-neutral interchange format, so your logic isn't locked into a single tool. Inspect the generated XML at any time from the built-in inspector.
How it works
- Step 1
Create a project
Sign up, create a project and pick a module. Everything is saved to your account automatically as you work.
- Step 2
Write and run your logic
Draw rungs or write Structured Text, then start the scan engine. Energised contacts and coils light up as the program runs.
- Step 3
Connect it to an I/O device
Bind tags to a simulated scene, an external 3D I/O simulator, or real devices through the Hardware Gateway and iterate until the machine behaves.
Who it's for
Students and instructors
Practise PLC programming without buying a trainer rack or licensing vendor software. Every student only needs a browser.
Automation engineers
Prototype control sequences, test edge cases with forced I/O, and validate logic against a virtual machine before commissioning.
Integrators and hobbyists
Bridge to Modbus and OPC UA devices on your bench for quick experiments, demos and proof-of-concept work.
Frequently asked questions
- Is Visual PLC Studio free?
- Yes, it's currently free to use. Create an account and you can start writing, simulating and testing PLC programs straight away.
- Do I need to install anything?
- No. The editors, compiler and scan engine all run in a modern desktop browser (Chrome, Edge or Firefox). You only install the optional Hardware Gateway agent if you want to talk to a 3D I/O simulator or physical devices over Modbus or OPC UA.
- Which PLC programming languages are supported?
- Ladder Diagram (LD) and Structured Text (ST), following the IEC 61131-3 standard. Function Block Diagram (FBD) and Sequential Function Chart (SFC) are coming in the near future.
- Can I use it to control real machinery?
- Visual PLC Studio is a development, training and simulation environment. It is not a safety-rated controller and must not be used as the control system for real equipment where failure could cause injury or damage. See our Terms and Conditions for details.
- Where is my project data stored?
- Projects are saved to your account so you can pick up where you left off on any computer. Read our Privacy Policy to see exactly what we store and why.
- Does it work with 3D I/O simulators?
- Yes. Run the Hardware Gateway agent on the same computer as your 3D simulator and add the scene as a Modbus TCP device (port 502 by default). Your program's tags then read the scene's sensors and drive its actuators on every scan.
- Which industrial protocols does the Hardware Gateway support?
- Modbus TCP (as a server for your running program, and as a client polling other devices), Modbus RTU over USB-serial adapters, and an OPC UA server. A live packet feed and telemetry charts help you debug the connection.
- Can I export my project?
- Yes. File ▸ Export IEC 61131-10 XML downloads the whole project as PLCopen XML, the vendor-neutral interchange format, and File ▸ Open project… loads an exported file back in.
Start building your first rung
Create an account and open Logic Studio in under a minute.