Guides
Cheat Sheet: Raspberry Pi GPIO
The 40 pins of the Raspberry Pi (all models with a 40-pin connector, from the Pi 1 B+ onwards). The Pi operates at 3.3 V: never connect 5 V to a GPIO pin. Use the button to print or save as PDF. An interactive version with search can be found in our GPIO pinout tool.
| Function | Pin | Pin | Function |
|---|---|---|---|
| 3.3 V | 1 | 2 | 5 V |
| GPIO2 (I2C SDA) | 3 | 4 | 5 V |
| GPIO3 (I2C SCL) | 5 | 6 | Ground (GND) |
| GPIO4 | 7 | 8 | GPIO14 (UART TX) |
| Ground (GND) | 9 | 10 | GPIO15 (UART RX) |
| GPIO17 | 11 | 12 | GPIO18 (PWM0) |
| GPIO27 | 13 | 14 | Ground (GND) |
| GPIO22 | 15 | 16 | GPIO23 |
| 3.3 V | 17 | 18 | GPIO24 |
| GPIO10 (SPI MOSI) | 19 | 20 | Ground (GND) |
| GPIO9 (SPI MISO) | 21 | 22 | GPIO25 |
| GPIO11 (SPI SCLK) | 23 | 24 | GPIO8 (SPI CE0) |
| Ground (GND) | 25 | 26 | GPIO7 (SPI CE1) |
| GPIO0 (ID EEPROM SD) | 27 | 28 | GPIO1 (ID EEPROM SC) |
| GPIO5 | 29 | 30 | Ground (GND) |
| GPIO6 | 31 | 32 | GPIO12 (PWM0) |
| GPIO13 (PWM1) | 33 | 34 | Ground (GND) |
| GPIO19 (PWM1, SPI1 MISO) | 35 | 36 | GPIO16 |
| GPIO26 | 37 | 38 | GPIO20 |
| Ground (GND) | 39 | 40 | GPIO21 |
Things to watch out for
- The pin number (1 to 40, the position on the board) is not the same as the GPIO number. Pin 3 is GPIO2.
- Pin 1 is on the SD card side, at the corner of the board. The odd pins are on the inside, the even ones on the outside.
- Keep the current per pin low (around 16 mA, together not more than around 50 mA). For an LED, use a resistor: see the LED resistor tool.
- GPIO0 and GPIO1 (pins 27 and 28) are intended for reading HAT boards; don’t use them for other things.
- You can make a 5 V signal safe for a GPIO with a voltage divider or a level shifter.
The functions in parentheses are the default functions; many pins can do more. Check the Raspberry Pi documentation for the exact behavior on your model.