Virtual Online Arduino Simulator - Wokwi Arduino Simulator


Topic: There are already a lot of Arduino simulators online. Unfortunately, most of them have been last updated several years before. A few are available but not for free. Here I have tried almost all Arduino Simulators and common problems are below 1. No support of external libraries 2. No support for assembly programming 3. runs on an outdated Arduino IDE 4. Very slow

I have been working with the wokwi Arduino simulator for some time, and I would like to share my experience of why it is a valid and workable solution presently for simulation needs.

  • The basic AVR8js compiler engine which runs the simulator is made open-source (
  • The execution happens on the browser itself yet without much lag (very fast, compared to older simulators)
  • Peripherals support - new ones are added frequently
  • A step towards practical things - For example - bounce feature is there for the switches
  • Quite a number of standard examples are there
  • Supports UNO, Mega, Nano, ATtiny85 and more will be added on request, soon
  • special peripherals such as ultrasonic sensors, NeoPixels, FastLEDs (matrix, strip and others) are supported
  • support is available (

many people have created applications based on the open-source AVR8js engine

I would request you to share your constructive criticism. This helps a lot to make this Free Arduino simulator, a practical tool too in the future

Hello all,

I would like to introduce a free Arduino simulator for all those people who are looking for a

  • faster simulator

  • simulator with lots of examples

  • Arduino simulator with the support team

  • The simulator can run flawlessly on Windows, macOS, and on mobiles as well

free Arduino simulator by wokwi

This Arduino simulator can be used by students to learn Arduino programming faster

It is very easy to share the project (just one click) with others. This enables easy code sharing as well. This also helps the teachers to create partial projects which students can take to complete.

All the interface are made free. There is no limitation (irritation) of limited simulation time or limited simulated parts. Hence, especially during the situation we all are in, this is a very good solution for remote classes.

Other benefits of the simulator

  • Free

  • faster simulations

  • multi-file projects are supported

  • Supports UNO, Mega, Nano, ATTiny85 as well

  • Supports a lot of peripherals and sensors

  • very easy to add third-party libraries and work with them

  • The projects are stored on the server. hence, they can be accessed anywhere, anytime via any device

  • Coding can be done on any PC with a browser. Many people are coding on their mobiles and tablets too,

  • No installations or downloads are necessary!

Example projects


Simon Game - A memory game with 4 push buttons

Diatonic Piano - A 8-note piano, use keys 1-8 to press the buttons and play the notes.

Bounce vs non-bounce - a good example of showing how a bounce in mechanical switches can create multiple ON-OFF conditions due to a single user press.

ARDUINO and LED projects

Blink - Arduino’s standard Blink sketch

ARDUINO and LCD1602, LCD2004 projects

LiquidCrystal Hello World

LiquidCrystal I2C Hello World

LiquidCystal Custom characters

Electronic Safe

DS1307 Clock

LCD2004 Tiny Pacman on Wokwi


Basic Keypad example

Arduino Calculator

Electronic Safe

Arduino SERVO MOTOR examples



ATTiny85 examples

ATtiny85 Blink

ATtiny85 Simon Game

ATtiny85 FastLED Matrix

ATtiny85 Charlieplexing

ATtiny85 SSD1306 + DHT

You can find a lot of Arduino library examples as well.

Got a suggestion? Need a hand?

People here on Discord for support

Please support this free Arduino simulator platform by testing, tinkering with other projects and also by giving feedback!

Thanks a lot. Please DM or reply with comments and let us know what you think!







Comparing Tinkercad to Wokwi by Koepel
Updated at 13 May 2021

Tinkercad Wokwi
Open source No Yes, the project is on Github βœ“
Drag and drop circuit Yes βœ“ Yes βœ“ (it needs some work)
Cheatsheet needed to build circuit No βœ“ Sometimes
Boards Uno, micro:bit Uno, Nano, Mega, ATtiny85 βœ“
(Raspberry Pi Pico coming soon)
Use any library No No, but the *.h and *.cpp files can be added as local files.
Two Arduino boards at the same time Yes βœ“ No
Debug Simple βœ“ I could not make it work
Visualy Okay βœ“ Okay βœ“
Website Demanding website
(slow on slow computer)
Fast website, but slow file access and file update
UTF-8 Not full support in the Serial Monitor Yes βœ“
Code speed 15% slower Same as the current Arduino IDE βœ“
:point_right: Simulation speed on slow computer Firefox 7%
Chrome 16%
Firefox 38% βœ“
Chrome 79% βœ“
Get a public permanent link to a project Yes, but very hard to find Yes, very easy βœ“
Code in multiple tabs No Yes βœ“
Programming in "Blocks" Yes βœ“ No
Development Very little Developing all the time βœ“
Fun to use
(is it behaving as expected)
Yes βœ“ Yes βœ“

I think that the Wokwi website is missing who is behind the project, how it started, and why was it made.

The Simulation speed was tested with math (calculating pi) and compared with a real Arduino Uno board with Arduino IDE 2.0.0-beta.5. The simulation was done in Windows 10 with Firefox 88 and Chrome 90 and I used my slowest computer for the test.
The Code speed was tested with millis() to measure calculating pi on a slow computer. Even if the computer could not run the simulation at full speed the resulting millis() value was the same in Wokwi as the real Uno board. Tinkercad was slower, perhaps because of other compiler options.
Both Tinkercad and Wokwi are Fun to use. The simulation in Wokwi is a lot faster, but it is possible to lose work when forgetting to click "Save".

Conclusion: At 3 May 2021 the drag and drop was introduced. The json file with the diagram is live updated. The base of the project is working. After fixing many details, it will be more useful than Tinkercad.
Tinkercad has each year only a few small improvements, therefor the Wokwi project will be my new favorite.