BenchTwin: The Most Advanced Microcontroller Simulator

Simulate Arduino, ESP32, Raspberry Pi Pico, STM32 and more, right in your browser. Put real parts on a 3D bench, wire them pin to pin, write the code and watch it run, before you buy a single part.

A microcontroller simulator that looks and works like your real bench

Most simulators draw flat pictures of circuits. BenchTwin puts every board and part on a 3D bench at its real size, with its pins where the real ones are, so what you build on screen is what you build on your desk.

• Real boards: Arduino Uno, Nano, Mega, Leonardo and Uno R4; ESP32, ESP32-S3, ESP32-C3 and ESP8266; Raspberry Pi Pico and RP2040; STM32, Teensy, nRF52 and ATtiny85.
• Real code: Arduino sketches run with setup() and loop(), digitalWrite, analogRead, PWM, interrupts, Serial, I²C and popular libraries for displays and sensors.
• Real parts: LEDs, buttons, sensors, OLED and TFT screens (including the round GC9A01), servos, motors, relays and batteries, on breadboards whose holes and strips work like real ones.
• Circuit checks: BenchTwin explains mistakes in plain words, like an LED without a resistor or 5 V on a 3.3 V pin, before anything burns.
• Lab tools: a multimeter, an oscilloscope and a pin timeline measure the circuit while it runs.

Arduino simulator

Wire an Arduino Uno or Nano to LEDs, buttons and sensors, write your sketch and press Simulate. LEDs light, servos turn, screens draw and the serial monitor talks back. When it works, BenchTwin gives you the shopping list, the wiring and the code for the real thing.

ESP32 simulator

Simulate the ESP32 DevKit and the newer ESP32-S3 and ESP32-C3 boards with their real pin rules: input-only pins, 3.3 V logic, ADC pins and the built-in LED on GPIO 2. Use Serial, PWM and I²C displays just like on the real board.

Raspberry Pi Pico simulator

Run Arduino-style code on the Raspberry Pi Pico and other RP2040 boards, with their own pin numbering and analog inputs.

Robot simulator for competitions

Build LEGO SPIKE, VEX, FTC and FRC robots from real parts, program them in the language your team uses, and test your autonomous on a competition field.

Learn with hands-on lessons

The BenchTwin course teaches wiring, breadboards and Arduino coding with a mini simulator next to every lesson: you do each step yourself, and each goal ticks off when you get it right.

Questions

Is BenchTwin a free microcontroller simulator?

Yes. BenchTwin runs in your browser and is free to use while it is in beta. You don't need to install anything or make an account; with a free account you can save projects to the cloud.

Which microcontrollers can I simulate?

Arduino boards (Uno, Nano, Mega, Leonardo, Micro, Pro Mini, Nano Every, Uno R4, Due and more), ESP32, ESP32-S2, ESP32-S3, ESP32-C3 and ESP8266 boards, the Raspberry Pi Pico and other RP2040 boards, STM32 Blue Pill and Nucleo boards, Teensy, nRF52 boards and the ATtiny85.

Can I simulate Arduino code online?

Yes. Write a normal Arduino sketch with setup() and loop(), press Simulate, and the code runs on the board you wired. Mistakes get plain-language error messages, and the serial monitor shows what your program prints.

What parts can I wire to the microcontroller?

Thousands of real parts: LEDs, resistors, buttons, potentiometers, sensors (light, temperature, distance, motion, gas), OLED and TFT displays, servos, motors, relays and batteries, on breadboards that work like real ones.

Can I simulate robots?

Yes. BenchTwin has LEGO SPIKE, VEX, FTC and FRC robot parts. Program them in SPIKE or VEXcode Python, FTC Java or FRC Java, and drive them on a competition field in the Test Bench, with real physics and the real time limit.

Do I need to install anything?

No. BenchTwin is a web app. It works in Chrome, Edge, Firefox and Safari on computers, Chromebooks, tablets and phones.