Web Serial Monitor

Almost every robot has a microcontroller somewhere, and the first debugging tool for a microcontroller is its serial port. The Web Serial Monitor brings a serial monitor and plotter to the browser, so you can talk to an Arduino or ESP32 from any computer with Chrome or Edge, without installing an IDE.

Features

• Connect at any common baud rate, with data bits, parity, stop bits and flow control.
• Timestamps, hex view, a line filter and pause, with a log you can save as a text file.
• Send text or raw hex bytes with your choice of line ending, with command history.
• A live plotter for comma- or space-separated numbers and named name:value pairs.
• A reset button that pulses RTS and DTR, which restarts most ESP32 and Arduino boards.
• A demo device that streams simulated sensor data, for trying the tool without hardware.

How it works

The page uses the Web Serial API, a browser standard that lets a web page open a serial port after you pick it in the browser's own permission dialog. The data goes straight from the device to the page and is never sent to a server. Firefox and Safari do not support Web Serial yet; they can still run the demo.

Open the Web Serial Monitor. The guides below cover the Web Serial API, baud rates and line endings, a robust serial protocol for ROS 2, fixing USB serial problems, and logging data.