About CircuitBench
CircuitBench is a free circuit simulator that runs entirely in your web browser. You place components on a workspace, wire them together, write Arduino-style code, and watch the circuit behave in real time. Nothing to install and no account is needed.
Why we built it
Learning electronics is much easier when you can experiment without fear of burning out an LED or shorting a battery. CircuitBench lets students, hobbyists and teachers try ideas quickly, see live voltages, and understand why a circuit works or fails, before touching real hardware.
What it can do
- Simulate resistors, LEDs, capacitors, diodes, transistors, buttons, potentiometers and more using a real nodal-analysis solver.
- Run Arduino C++ sketches on boards such as Arduino and ESP32, with a built-in serial monitor.
- Show live pin voltages and an oscilloscope-style scope for any pin.
- Check your wiring for floating or miswired pins.
- Save circuits in your browser, or import and export them as files.
- Load ready-made examples: blinking LEDs, servo sweeps, NeoPixels, LCD displays, motors and ultrasonic sensors.
How the simulation works
The engine uses modified nodal analysis (MNA) to solve node voltages. Non-linear parts such as diodes are solved with Newton-Raphson iteration, and capacitors use backward-Euler time stepping. It is designed for learning and is an approximation, so always double-check real builds against datasheets.
Learn more
Explore the component library, the electronics basics and the Arduino C++ tutorial.
Contact
Questions, bug reports or ideas? See our contact page.