ESP32 partition table editor

Lay out the flash of an ESP32: start from a preset or your own partitions.csv, change partitions in the table or on the map, and see at once whether it fits, whether OTA works and whether your app has room. Save the CSV, or the binary table, byte for byte what gen_esp32part.py makes.

The rules it checks

• App partitions start on a 64 KB boundary (0x10000) and their size is a multiple of 4 KB; data partitions start on a 4 KB boundary.
• Nothing starts below the end of the partition table (0x9000 with the table at 0x8000), and no two partitions overlap.
• One otadata partition of exactly 8 KB when there are OTA slots, and two slots for an update to have somewhere to go.
• A writable NVS partition of at least 12 KB (0x3000); WiFi and the PHY calibration need one.
• The table fits the flash size, and your app fits the smallest app partition, with room to grow.

Using it in a project

• ESP-IDF: save partitions.csv in the project folder, and in menuconfig set Partition Table to Custom, file partitions.csv.
• Arduino: put partitions.csv next to the .ino; Arduino ESP32 core 2.0.6 and later uses it instead of the scheme in the Tools menu.
• PlatformIO: board_build.partitions = partitions.csv in platformio.ini.

Changing the partition table of devices in the field is risky: the bootloader and the app must agree on it, and an OTA update cannot change it safely. Plan the layout, with two OTA slots, before the first device ships. The field support checklist.

Try it

Three devices are free, and no card is needed. Create an account, or read the five-minute guide first.

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