WebUSB ❤ ️Arduino

This repository contains an Arduino library for WebUSB-enabling your sketches. Example sketches and JavaScript code are available in the demos directory.

The WebUSB object is a copy of the Arduino SDK’s built-in USB serial library. It creates a WebUSB-compatible vendor-specific interface rather than one marked as USB CDC-ACM. This prevents operating system drivers from claiming the device and making it inaccessible to the browser. This library also implements:

Compatible Hardware

WebUSB requires an Arduino model that gives the sketch complete control over the USB hardware. This library has been tested with the following models:

Getting Started

  1. Install at least version 1.6.11 of the Arduino IDE.

  2. The WebUSB library provides all the extra low-level USB code necessary for WebUSB support except for one thing: Your device must be upgraded from USB 2.0 to USB 2.1. To do this go into the SDK installation directory and open hardware/arduino/avr/cores/arduino/USBCore.h. Then find the line #define USB_VERSION 0x200 and change 0x200 to 0x210. That’s it!

macOS: Right click on the Arduino application icon and then click on show package contents menu item. Navigate to Contents/Java/hardware/arduino/avr/cores/arduino/USBCore.h

Warning: Windows requires USB 2.1 devices to present a Binary Object Store (BOS) descriptor when they are enumerated. The code to support this is added by including the “WebUSB” library in your sketch. If you do not include this library after making this change to the SDK then Windows will no longer be able to recognize your device and you will not be able to upload new sketches to it.

  1. Copy (or symlink) the library/WebUSB directory from this repository into the libraries folder in your sketchbooks directory.

  2. Launch the Arduino IDE. You should see “WebUSB” as an option under “Sketch > Include Library”.

  3. Load up demos/rgb/sketch/sketch.ino and program it to your device.

  4. When the sketch is finished uploading you should see a notification from Chrome: “Go to to connect.” Try it out!

Windows: This notification is currently disabled in Chrome on Windows due to Chromium issue 656702. Implementation of new, more stable USB support for Windows is tracked on Chromium issues 422562 and 637404.

Android: This notification is not supported on Android because of OS limitations that prevent the browser from connecting to a device without user interaction.

Adding New Boards of Supported Architecture

  1. Plug in your board.
  2. Run lsusb and find your boards vendor ID and product ID
    Example: Bus 001 Device 119: ID 2341:805a Arduino SA where 0x2341 is vendor ID and 0x805a is product ID.
  3. Add your board’s vendor ID and product ID to the filters in serial.js file -
    const filters = [
       { 'vendorId': 0x2341, 'productId': 0x8036 }, // Arduino Leonardo
       { 'vendorId': 0x2341, 'productId': 0x8037 }, // Arduino Micro
       { 'vendorId': 0x2341, 'productId': 0x804d }, // Arduino/Genuino Zero
       { 'vendorId': 0x2341, 'productId': 0x804e }, // Arduino/Genuino MKR1000
       { 'vendorId': 0x2341, 'productId': 0x804f }, // Arduino MKRZERO
       { 'vendorId': 0x2341, 'productId': 0x8050 }, // Arduino MKR FOX 1200
       { 'vendorId': 0x2341, 'productId': 0x8052 }, // Arduino MKR GSM 1400
       { 'vendorId': 0x2341, 'productId': 0x8053 }, // Arduino MKR WAN 1300
       { 'vendorId': 0x2341, 'productId': 0x8054 }, // Arduino MKR WiFi 1010
       { 'vendorId': 0x2341, 'productId': 0x8055 }, // Arduino MKR NB 1500
       { 'vendorId': 0x2341, 'productId': 0x8056 }, // Arduino MKR Vidor 4000
       { 'vendorId': 0x2341, 'productId': 0x8057 }, // Arduino NANO 33 IoT
       { 'vendorId': 0x239A, 'productId': 0x000E }, // Adafruit ItsyBitsy 32u4
       { 'vendorId': 0x239A, 'productId': 0x800D }, // Adafruit ItsyBitsy 32u4
  4. Try connecting !


  1. Connect your board
  2. Load the sketch onto your board
  3. Open the landing URL
  4. Inspect the page and goto Sources
  5. Open serial.js in the inspector and add your vendor ID and product ID and don’t forget to save - press Ctrl+S
  6. Press Connect and hopefully it works!