SketchSketch32 Pro
Unlimited simulation and uploads, no ads.
New · Circuit simulator
Run Arduino even without a board
Build your circuit on a breadboard with your finger and run your code: LEDs light up, the servo turns, the LCD prints. It is exactly the same code you would upload to the board.
What you get
A real circuit, real code
The simulator does not imitate your code; it runs the compiled program instruction by instruction, like the Arduino's processor.
- 01 Write the code In the editor or right in the simulator.
- 02 Build the circuit Put parts on the breadboard and draw the wires.
- 03 Run it The code compiles, the circuit comes alive and the serial monitor shows the output.
Real-time execution
Your code is compiled for the Arduino Uno by the compiler on your phone and runs at processor level. delay, millis, Serial, analogRead, interrupts and libraries behave like the real thing.
Finger-friendly breadboard
Drag parts into the holes and draw wires from hole to hole with your finger. A magnifier shows the target hole and the connected strip lights up green.
Real electrical model
Current and voltage are actually calculated. An LED without a resistor burns out; a 5V–GND short and too much pin current raise a warning.
Several boards
More than one board in the same circuit, each with its own code. Boards talk to each other over serial.
Ready-made parts
LED, RGB LED, resistor, push button, potentiometer, light sensor, buzzer, servo, ultrasonic sensor, I2C LCD, switch, Arduino Uno and Nano.
A guide for every part
What it does, its pins, how it goes on the breadboard, example code and common mistakes. Try it in the simulator with one tap.
Made for the classroom
Teach Arduino without a board, wires and parts for every student. Students are not afraid of mistakes: the simulator explains why the LED burned out, and no real part gets damaged.
Plans
The simulator is included in your plan
In the free version a simulation run uses the same 5 weekly credits as uploading to a board. With Pro and Pro Max simulation is unlimited.
The simulator was added to the current plans at no extra cost. Our prices may be updated in the future; lock in today's price for 12 months with a yearly plan.
Sketch32 Pro Max
Everything in Pro + more AI credits.
About the simulator
Is the simulator free?
In the free version every run uses one credit; the 5 weekly credits are shared with uploads. Pro and Pro Max are unlimited.
Which boards are simulated?
Arduino Uno and Arduino Nano today. We are working on the Mega and the ESP32 family.
Do I need the internet?
Compiling and simulation run on your phone and your code is never sent anywhere. The free version needs a connection for ads; Pro does not.
Can I use libraries?
Yes. Libraries such as Servo, Wire, EEPROM and LiquidCrystal_I2C work in the simulator just like on a real board.
Will code that works in the simulator work on a real board?
Yes. The simulator runs the very same program that gets uploaded to the board. Just choose "Upload to a real board" when you open the project.