SERIALFLOW TERMINAL / WEB
Web serial monitor. Debug in your browser.
SerialFlow Terminal Web is an online serial monitor for embedded developers. It uses the Web Serial API in desktop Chrome or Edge to connect USB serial devices, inspect ESP32 and other device logs, search and filter output, send AT commands or hex bytes, and copy or export logs without installing a desktop app. Serial data stays between your browser and the device.
Open the web serial monitorNo device handy? Try a virtual device in the workspace.
01 / WORKFLOW
Built for desktop debugging
01 / CONNECT
Choose a port and baud rate, then connect to a USB serial device from your browser.
02 / INSPECT
Filter and search live logs with timestamps and Text, Raw Hex, ESP-IDF or Modbus decoding.
03 / SEND
Send text or hex bytes, save frequent commands, and copy or export your logs.
How do you debug a serial device in the browser?
- Connect your device to your computer over USB. Check that the operating system recognizes its serial port; if not, check the data cable and USB-to-serial driver.
- Open the web serial workspace in desktop Chrome or Edge, choose to connect a device, and grant access to the correct port in the browser prompt.
- Set the baud rate and serial parameters to match your device firmware, then connect.
- Inspect live logs, search and filter output, and send text or hex commands. Copy or export logs when you need to keep the output.
Web serial monitor FAQ
Which browsers support the web serial monitor?
Use desktop Chrome or Edge with Web Serial API support over HTTPS. Firefox, Safari and most mobile browsers cannot connect directly to serial devices. You can still try a virtual device in the workspace without a compatible browser.
Can I monitor ESP32 logs or send AT commands?
Yes. If your device exposes a serial port recognized by your operating system, select its baud rate to read logs and send text AT commands or hex bytes. The web app supports Text, Raw Hex, ESP-IDF log and Modbus decoding. It is a serial debugging tool, not an ESP firmware flasher.
Why is my serial port missing or unable to connect?
Check the USB data cable, device power and USB-to-serial driver, and close other serial tools that may be using the port. Use desktop Chrome or Edge over HTTPS and grant access to the correct port in the browser prompt.
How do I fix garbled serial output?
Match the baud rate, data bits, stop bits and parity to the device firmware. Use Text mode for text logs; for binary data, switch to Raw Hex or the appropriate protocol decoder.
Can I try it without hardware or connect from Android?
Choose a virtual device in the web workspace to try log viewing, search and filtering without hardware. For direct USB-OTG serial connections on an Android phone, use SerialFlow Terminal for Android. The web app is intended primarily for desktop browsers.
Before you connect
Use desktop Chrome or Edge over HTTPS. Your browser will ask for port permission on the first connection. Firefox, Safari and most mobile browsers cannot connect directly, but you can try a virtual device.
Open the web serial monitor ↗On a phone or tablet? The Android app connects to USB-OTG devices directly.
Get SerialFlow Terminal for Android ↗