Pikoo Shrinks the Raspberry Pi Pico Without Sacrificing GPIO

If you’re in the market for a pint-sized RP2040-based development board, there are lots of options. Many of them are the size of a postage stamp, so you can stick them just about anywhere you need to squeeze in some embedded computing horsepower. However, these tiny development boards have a pared-down form factor, leaving out lots of GPIO pins that you may need to interface with your circuit.

For those that need the full Raspberry Pi Pico pinout, but in a smaller-form-factor design, there is now a new option: the Pikoo. It is an ultra-slim RP2040 development board, but much slimmer—the width of the board has been shaved down from 21 mm to just 15 mm. The only other notable difference is the inclusion of a USB-C connector, which is something most people wish Raspberry Pi would have used in their own board design.

Pikoo uses the same RP2040 dual-core Cortex-M0+ microcontroller, running at up to 133 MHz with 264 KB of on-chip SRAM as the official board. The full 40-pin, 2.54 mm header layout matches the Raspberry Pi Pico exactly, meaning existing hardware designs and firmware can be reused without modification. If code runs on a Pico, it will run on Pikoo as well.

Despite its slimmer profile, nothing has been removed or emulated. Pikoo exposes the full set of RP2040 peripherals, including up to 30 GPIOs with SPI, I2C, UART, PWM, and access to the chip’s powerful programmable I/O (PIO) blocks. These PIO state machines allow for precise, timing-critical signal generation and protocol handling, enabling control of everything from NeoPixels and LED matrices to custom serial buses and display interfaces.

USB is handled directly by the RP2040’s native full-speed USB 1.1 controller, enabling UF2 drag-and-drop programming, USB CDC serial, HID devices, and custom USB classes without the need for an external USB-to-serial chip. A standard 12 MHz crystal and reference clock design ensure stable USB operation and predictable timing for real-time applications.

On the software side, Pikoo benefits from the massive RP2040 ecosystem. It supports MicroPython, CircuitPython, the official Raspberry Pi Pico SDK for C and C++, and the Arduino IDE. This makes it accessible to beginners while still offering the low-level control required by advanced users.

By combining full Pico compatibility with a slimmer, enclosure-friendly design, Pikoo fills a niche for projects that need every pin the Pico offers, but none of the extra bulk. If that matches your needs, you can pick one up on Kickstarter for about $14.