A WebSocket Server and Client library for Arduino, based on RFC6455, for writing modern Websockets applications.
Featuring modern callbacks (supports lambdas) and a minimal interface. Contains a websockets Client and Server. Supports all features of the RFC6455 (pings, pongs, binary and text data, error codes) and WSS (Websockets over SSL). Now support ESP8266, ESP32 (including ESP32-C3; ESP32-S2 Saola, AI-Thinker ESP-12K, WT32_ETH01, etc.), nRF52, SAMD21, SAMD51, SAM DUE, STM32F/L/H/G/WB/MP1, Teensy, RP2040-based, Portenta_H7, etc. boards, with WiFiNINA, Teensy 4.1 NativeEthernet/QNEthernet, Ethernet W5x00/ENC28J60/LAN8742A/LAN8720, ESP8266/ESP32-AT modules/shields, Portenta_H7 WiFi/Ethernet, as well as SINRIC / Alexa / Google Home. With updated SSL CA Certs, Fingerprint and InSecure mode.

Author: Gil Maimon

Maintainer: Khoi Hoang

Read the documentation


This library is compatible with all architectures so you should be able to use it on all the Arduino boards.


To use this library, open the Library Manager in the Arduino IDE and install it from there.