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ESPTOOL.PY(1) User Commands ESPTOOL.PY(1)


esptool - ESP8266 and ESP32 ROM Bootloader Utility


usage: esptool [OPTION] COMMAND

command arguments:

Download an image to RAM and execute
Dump arbitrary memory to disk
Read arbitrary memory location
Read-modify-write to arbitrary memory location
Write a binary blob to flash
Run application code in flash
Dump headers from a binary file (bootloader or application)
Create an application image from binary files
Create an application image from ELF file
Read MAC address from OTP ROM
Read Chip ID from OTP ROM
Read SPI flash manufacturer and device ID
Read SPI flash status register
Write SPI flash status register
Read SPI flash content
Verify a binary blob against flash
Perform Chip Erase on SPI flash
Erase a region of the flash
Merge multiple raw binary files into a single file for later flashing
Get some security-related data
Print esptool version


show this help message and exit
Target chip type
Serial port device
Serial port baud rate used when flashing/reading
What to do before connecting to the chip
What to do after esptool is finished
Disable launching the flasher stub, only talk to ROM bootloader. Some features will not be available.
Enable trace-level output of esptool interactions.
Override ESP32 VDDSDIO internal voltage regulator (use with care)
Number of attempts to connect, negative or 0 for infinite. Default: 7.


Display device features, SPI flash manufacturer and device ID:

esptool flash_id

Flash ESP8266 Espressif AT v1.6.2 firmware to ESP-WROOM-02 board:

esptool write_flash --flash_mode dio --flash_size 4MB-c1 0x00 boot_v1.7.bin 0x1000 at/1024+1024/ 0xfe000 blank.bin 0x3fc000 esp_init_data_default_v08.bin 0x3fe000 blank.bin

Flash ESP32 Espressif AT v1.1.1 firmware to ESP-WROOM-32 board:

esptool write_flash --flash_mode dio --flash_freq 40m --flash_size detect 0x1000 bootloader/bootloader.bin 0x20000 at_customize.bin 0x21000 customized_partitions/ble_data.bin 0x24000 customized_partitions/server_cert.bin 0x26000 customized_partitions/server_key.bin 0x28000 customized_partitions/server_ca.bin 0x2a000 customized_partitions/client_cert.bin 0x2c000 customized_partitions/client_key.bin 0x2e000 customized_partitions/client_ca.bin 0xf000 phy_init_data.bin 0x100000 esp-at.bin 0x8000 partitions_at.bin

Display ESP32 efuse state summary:

espefuse --port /dev/ttyUSB0 summary

Generate a flash encryption key:

espsecure generate_flash_encryption_key key.bin

Burn the key to the device (WARNING: one time only operation):

espefuse --port /dev/ttyUSB1 burn_key flash_encryption key.bin

Encrypt flash data:

espsecure encrypt_flash_data --keyfile key.bin --address 0x10000 -o my-app-encrypted.bin my-app.bin

AUTHOR was started by Fredrik Ahlberg as an unofficial community project, currently maintained by Angus Gratton and supported by Espressif Systems (Shanghai) PTE LTD. This manual page has been produced by Milan Kupcevic <> for the Debian project and can be used by others.


Review: <>
Known issues: <>
Report new issues at: <>


Copyright © 2014-2017 Fredrik Ahlberg, Angus Gratton, Espressif Systems (Shanghai) PTE LTD, other contributors as noted. License GPLv2+: GNU GPL version 2 or later <>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.


esptool(1), espefuse(1), espsecure(1)

January 2024 4.7.0