WebUSB API
Enables web-based firmware updates, microcontroller programming (Arduino, ESP32), and custom USB device control without native drivers. Chrome-only but the only web path to raw USB access.
What It Defines
Defines navigator.usb.requestDevice() for accessing USB devices from the browser. Supports device filters (vendorId, productId), configuration/interface/endpoint selection, and control/bulk/interrupt/isochronous transfers. User-driven device picker provides the security model.
Canonical (Normative)
Convenient (Practical)
Publishes web platform specs including CSS, accessibility, security policies, Service Workers, Web App Manifest, and many browser APIs. Also maintains some versioned HTML/DOM specs.
Related Specs
Enables web-based communication with serial devices: Arduino/microcontroller consoles, GPS receivers, lab equipment, POS terminals, and CNC machines. Uses the Streams API for data flow.
Enables web apps to access HID devices that the Gamepad API doesn't cover: custom controllers, macro pads, LED strips, barcode scanners, and specialized input devices. Complements Gamepad API for non-standard controllers.
The gating mechanism for every sensitive browser API. Check permission state before requesting access to avoid unexpected prompt dialogs. The change event lets you react when users revoke permissions in browser settings.