EMBEDDED TOOL
Arduino Board Pinout Reference (Extended)
Pinouts for Leonardo/Micro, Due, Pro Mini, ATtiny85, ESP32-C3/S3.
About this tool
A searchable pin reference for popular Arduino-ecosystem boards beyond the basics — Leonardo/Micro (32u4, with native USB and its own interrupt map), Due, Pro Mini, the tiny ATtiny85, and the newer RISC-V/Xtensa-S3 ESP32 variants. Filter by pin name or function to quickly find which pin does what.
Frequently asked questions
- How is this different from the general Microcontroller Pinout Reference?
- That tool covers the most common starting boards (Uno, Nano, Mega, ESP32, ESP8266, Blue Pill). This one covers boards you'll reach for next — the 32u4-based Leonardo/Micro with native USB, the ARM-based Due, the bare-bones Pro Mini, the tiny ATtiny85, and the current ESP32-C3/S3 variants.
- Why does the ATtiny85 only have 5 usable I/O pins?
- It's an 8-pin chip — two pins are power (VCC/GND) and one is typically reset, leaving 5 (sometimes 6, if reset is repurposed via a fuse setting) general-purpose I/O pins, several of which double as PWM or ADC.
- What's different about ESP32-C3 vs the original ESP32?
- The C3 uses a single-core RISC-V processor instead of Xtensa, has fewer GPIOs, and remaps several strapping pins — don't assume pin numbers carry over from ESP32 or ESP32-S3 designs.