BROWSER-BASED FIRMWARE TOOL

ESP32 Web Flasher

Flash trusted firmware to your ESP32 directly from your browser. No installer, no account, and your firmware file stays on your device.

✓ Web Serial✓ SHA-256 check✓ Local file support

Before you start

Use a USB data cable and a supported desktop version of Chrome or Edge. Flashing overwrites firmware and can make a board temporarily unusable if the wrong image or address is chosen. Only flash firmware from a source you trust.

STEP 01

Prepare firmware

Firmware category Target board

Firmware binary (.bin)Required

↑Choose a firmware fileSelect a local .bin file. Nothing uploads to a server.Browse

Flash addressHexadecimal

0x10000 is common for an application-only image. Complete firmware packages can require multiple files at different addresses. Confirm the address in your firmware project's official instructions.

Expected SHA-256 Optional

If supplied, the hash must match before flashing. A matching hash proves file integrity against that value, not that the source is trustworthy.

Compatibility matters. This tool cannot reliably identify every firmware's target board or partition layout from a single .bin file. Do not proceed unless the firmware publisher documents the target and flash address.

STEP 02

Connect your board

Not connected

No device detected

Connect your ESP32 with a USB data cable, then choose Connect device.

Connection baud rate

Your browser will show a port picker. Select the USB serial device. On Windows, a CH340 driver may be needed if no port appears.

STEP 03

Flash firmware

I understand flashing writes to the ESP32 and may overwrite existing firmware or data.

The flash button becomes available only when a device is connected, a file is selected, and the overwrite confirmation is checked.

Waiting to flash0%

Progress will appear during the real flashing operation.

LIVE DIAGNOSTICS

Status & troubleshooting

Ready when you are

Choose a firmware file and connect your ESP32 to begin.

Activity log

[INFO] Page loaded. Hardware has not been tested in this environment.

⌘

Port not showing?

Try another USB data cable and USB port. Close other serial-monitor apps. Install the correct USB-to-serial driver, such as CH340 or CP210x, if required.

↻

Connect failed?

Some boards need manual boot mode. Hold BOOT, click Connect, and release BOOT when connection begins. Button timing differs by board.

⚑

Flash failed?

Confirm the board model, firmware source, flash address, and USB cable. Do not disconnect power while writing. Reconnect and retry only after checking the publisher's instructions.