Compatible Boards
Requirements
- Chip: one of the chips listed under Chip support
- Flash: at least 4 MB
RAM is determined by the chip and module: 384-520 KB of internal SRAM, shared by the runtime, WiFi/BLE stacks, your app, and every loaded module. PSRAM variants (ESP32-S3, ESP32-C5, ESP32 WROVER) add external SPI memory in the same package, which lets larger apps use memory beyond the SRAM budget.
Chip support
| Chip | Notes |
|---|---|
| ESP32‑C6 | Recommended. Primary development chip. WiFi 6, BLE 5, Thread/Zigbee. |
| ESP32‑S3 | Recommended. PSRAM variants fit larger apps. |
| ESP32‑C5 | Recommended. Dual-band WiFi 6 and BLE 5. Requires PSRAM for the standard Mikro.js configuration (WiFi + BLE concurrently); 5 GHz needs wifi.country set. |
| ESP32 | Supported. Prefer WROVER variants (4-8 MB PSRAM) over WROOM. On a board without PSRAM, flash the image without BLE (mikro flash --features no-ble): Bluetooth reserves more than 50 KB of RAM at startup, even when the app never uses it. An app that uses BLE but not WiFi gets 17 KB more with the image without WiFi (mikro flash --features no-wifi), and an app that uses neither radio gets the most RAM with mikro flash --features min. |
| ESP32‑C3 | Limited support. Good fit for GPIO, timers, sensors, and BLE. Not enough RAM for HTTPS or memory intensive applications. |
Tested
| Board | Chip | Flash | PSRAM | Link |
|---|---|---|---|---|
| Seeed Studio XIAO ESP32C6 | ESP32‑C6 | 4 MB | - | seeedstudio.com |
| Seeed Studio XIAO ESP32S3 | ESP32‑S3 | 8 MB | 8 MB | seeedstudio.com |
| Seeed Studio XIAO ESP32C5 | ESP32‑C5 | 8 MB | 8 MB | seeedstudio.com |
| Seeed Studio XIAO ESP32C3 | ESP32‑C3 | 4 MB | - | seeedstudio.com |
Other boards
Any board with a supported chip and at least 4 MB flash should work, regardless of manufacturer: Adafruit, SparkFun, Waveshare, LILYGO, WeAct, generic DevKits. If you try one, let us know.
The generic ESP32-S3 firmware is built for octal PSRAM (N8R8, N16R8). S3 boards with quad PSRAM, such as N8R2, run without their PSRAM on it and need a board package or custom firmware to use it; see Troubleshooting.