Reference

ESP32-S3 Zero / Super Mini Pinout

The real pin reference for the ESP32-S3-Zero-style board: a coin-sized ESP32-S3 devkit sold under names like "ESP32-S3 Zero" and "ESP32-S3 Super Mini" by Waveshare and several other sellers.

21 september 2026 2 min read

Boards sold as “ESP32-S3 Zero” or “ESP32-S3 Super Mini” are near-identical coin-sized ESP32-S3 breakouts from several sellers, Waveshare’s own ESP32-S3-Zero is the most established and best-documented version, this guide is sourced from Waveshare’s own documentation. If your specific board came from a different seller, double-check its silkscreen labels against the table below before wiring anything, minor differences between clones are common.

System-on-chip and board

Built around the same ESP32-S3 chip as this site’s AI-S3 board: dual-core Xtensa LX7, Wi-Fi 802.11 b/g/n, Bluetooth 5 LE, native USB. This specific board is 23.5×18mm, single USB-C port, an onboard WS2812 addressable RGB LED, a BOOT button, and 4MB flash with 2MB of quad-SPI PSRAM (must be explicitly enabled in firmware, it isn’t used automatically).

GPIO reference

GPIO	Function	Notes
0	BOOT button	Hold low while connecting USB to enter download mode
1, 2, 4–8, 15–18, 38	General-purpose, ADC-capable	12 pins with no boot/system duties, safe first choice for your own wiring
3, 9–14	Strapping pins	Configure boot behavior at reset, avoid unless you know what you’re changing
21	WS2812 RGB LED	Onboard, addressable status LED
33–37	Not exposed	Reserved internally for octal PSRAM, not broken out to a header pin at all on this board
39–42	JTAG (TCK/TDO/TDI/TMS)	Usable as plain GPIO if you don’t need hardware debugging
43, 44	UART0 TX/RX	To onboard USB-serial converter
45	Strapping (flash voltage)	Avoid driving externally at power-on

Real gotchas

GPIO33–37 genuinely don’t exist on this board’s header, even though the ESP32-S3 chip itself has them, they’re wired internally to the onboard PSRAM. Don’t design around them being available, unlike some other ESP32-S3 boards that do expose them.
PSRAM isn’t automatic. The 2MB of onboard PSRAM only becomes usable once your build explicitly enables it (in Arduino IDE: Tools → PSRAM → “OPI PSRAM”; in ESP-IDF: the relevant `menuconfig` option).
Seller variation. Because “ESP32-S3 Zero” and “ESP32-S3 Super Mini” aren’t a single manufacturer’s trademarked product, always check your specific board’s silkscreen against this table rather than assuming an exact match.

Conclusion

This is the smallest, cheapest way to get a full ESP32-S3 with native USB and PSRAM onto a breadboard. For a larger board with dual USB-C and a built-in USB-serial adapter dedicated purely to flashing, see the AI-S3.