Quick Answer
The Seeed Studio XIAO is a family of thumb-sized development boards, named after the Chinese word for "small". Running on various microcontrollers including the nRF52840, ESP32, RP2040, and SAMD21, they are built for embedded projects, wearables, IoT devices, and rapid prototyping. Despite measuring just 21 x 17.8mm, each board includes USB-C, Arduino compatibility, and, in most variants, wireless connectivity.
What is the Seeed Studio XIAO?
The name says it all. XIAO (小) means "small" in Chinese, and these boards are among the smallest Arduino-compatible dev boards you can buy. The entire family shares a standardised 21 x 17.8mm footprint with castellated holes for soldering directly onto a PCB. Swap between chip families without redesigning your board layout.
Every XIAO ships with USB-C for power and programming. The single-sided SMD design puts all components on one face, making surface-mount integration straightforward for production runs.
Software support is broad. The Arduino IDE works out of the box for all boards, and most variants also run MicroPython, CircuitPython, Zephyr RTOS, and TinyGo. Whether you prefer writing C++ sketches, Python scripts, or Rust firmware, there is a toolchain ready to go.
The XIAO Family: Which Chip for Which Project?
With over a dozen variants available, the XIAO family covers nearly every maker use case. Here are the five boards you are most likely to reach for:
| Variant | Chip | Best For | Wireless |
|---|---|---|---|
| XIAO nRF52840 | Nordic nRF52840 | BLE devices, Meshtastic, low-power IoT | BLE 5.4, NFC |
| XIAO nRF52840 Sense | Nordic nRF52840 | TinyML, wearables with motion/audio | BLE 5.4, NFC |
| XIAO ESP32-S3 | Espressif ESP32-S3 | Wi-Fi projects, edge AI | Wi-Fi + BLE |
| XIAO RP2040 | Raspberry Pi RP2040 | General purpose, MicroPython | None |
| XIAO SAMD21 | Microchip SAMD21 | Arduino beginners | None |
Seeed has also released newer boards based on the ESP32-C6 (Wi-Fi 6, Zigbee, Thread), the RP2350, and the Silicon Labs MG24 (Matter-ready). For a deeper comparison of the nRF52840 variants specifically, see our XIAO nRF52840 vs XIAO nRF52840 Sense guide.
What Can You Build?
The XIAO's tiny size makes it ideal for projects where space is tight but capability matters.
- Mesh networking nodes: The XIAO nRF52840 pairs with the Wio-SX1262 LoRa module for Meshtastic. The Meshtastic Kit bundles everything you need to get started with off-grid communication.
- TinyML projects: The XIAO nRF52840 Sense Plus has a 6-axis IMU and PDM microphone onboard, making it ready for gesture recognition and audio classification without wiring extra sensors.
- Smart watch / wearable display: Pair any XIAO with the Round Display for Seeed Studio XIAO, a 1.28-inch touch screen with RTC, SD card slot, and battery charging built in.
- BLE peripherals: The XIAO nRF52840 Plus gives you 20 GPIOs and extra interfaces for building complex Bluetooth devices.
- IoT sensor networks: ESP32 variants add Wi-Fi, letting you build connected sensor nodes that report data to the cloud.
- Split keyboards: The nRF52840's BLE support makes it a popular choice for wireless split mechanical keyboards.
The Grove Ecosystem
XIAO boards connect to Seeed's Grove modular system through the XIAO Expansion Board, which adds standardised 4-pin connectors for plug-and-play prototyping. With over 400 Grove modules covering sensors, actuators, displays, and networking, you can build complex projects without touching a soldering iron.
Getting Started
The Arduino IDE is the fastest route to your first XIAO project. Install the relevant board package, select your variant from the Tools menu, and you are ready to upload. For a walkthrough, read our Getting Started with XIAO nRF52840: Arduino Setup guide. Browse the full XIAO range in our maker collection.
FAQ
Q: Is the Seeed Studio XIAO compatible with Arduino?
A: Yes. All XIAO boards work with the Arduino IDE out of the box. Most also support MicroPython, CircuitPython, and Zephyr RTOS.
Q: Can the XIAO nRF52840 run Meshtastic?
A: Yes. Pair it with the Wio-SX1262 LoRa expansion board and flash Meshtastic firmware. See our Meshtastic setup guide for step-by-step instructions.
Q: How small is the XIAO?
A: Just 21 x 17.8mm, roughly the size of a thumbnail. Despite the tiny footprint, every board includes USB-C and castellated holes for soldering directly onto a PCB.