Guide to Raspberry Pi Zero GPIO Pinout & Specifications

Last updated on March 14th, 2024 at 11:32 am

Raspberry Pi is a mini single-chip computer. It is developed by the Raspberry Pi Foundation in the United Kingdom along with the association of Broadcom. It is the smallest chipset in the Raspberry Pi series and is 40% faster than the original Raspberry Pi but nearly half of its size.

Raspberry Pi Zero
Raspberry Pi Zero                                                  

The Raspberry Pi Zero supports mini connectors (like mini HDMI, mini USB power, and USB on-the-go port) to save more space. And the 40pin GPIO is unpopulated which provides the flexibility to use only the connections that the project requires. It consists of a 1GHz BCM2835 single-core processor, 512 MB RAM, mini-HDMI, USB On-The-Go ports, and a camera connector.

Note: The Raspberry Pi Zero and Zero w have a mini HDMI port, not a micro HDMI one. 


Detailed features and specifications of R-Pi zero are given below:

ProcessorBCM2835 single-core processor :1GHz ARM11 core
Connectivity• 2 × USB 2.0 interface with OTG
• HAT-compatible 40-pin I/O header footprint
• MicroSD card slot
• Mini HDMI port
• CSI camera connector
Video• HDMI interface
• Composite video
Input power5V DC 2.5A
Form Factor65mm × 30mm × 5mm
R-pi Zero technical specifications

Raspberry pi Zero GPIO pinout

R-Pi Zero board layout
R-Pi Zero board layout

**Download the HD pinout image from here                                                          

One powerful feature of the Raspberry Pi is the row of GPIO (general-purpose input/output) pins along the extreme right edge of the board. Like every Raspberry Pi chipset, Zero consists of a 40-pin GPIO.

The standard interface for connecting a single-board computer or microprocessor to other devices is through General-Purpose Input/Output (GPIO) pins. GPIO pins do not have a specific function and can be customized using the software.

Some of the popular GPIO pin functions are given below:

Pin TypeGPIO pinsDescription
PWM pins GPIO12, GPIO13, GPIO18, GPIO19Used for Pulse Width Modulation
Used for Serial Peripheral Interface
I2C pinsData: (GPIO2), Clock: (GPIO3)
Used for Inter-Integrated Circuit communication
UART pinsTX: (GPIO14)
RX: (GPIO15)
To communicate between two microcontrollers or the computers.
GPIO pinout of the board

R- pi zero GPIO pinout Diagram
R- pi zero GPIO pinout diagram

Power pins

The board consists of two 5V pins, two 3V3 pins, and 9 ground pins (0V), which are unconfigurable.

5V: The 5v pins directly deliver the 5v supply coming from the mains adaptor. This pin can be used to power up the Raspberry Pi zero, and it can also be used to power up other 5v devices.

3.3V: The 3V pin is there to offer a stable 3.3V supply to power components and to test LEDs.

GND: Ground is commonly referred to as GND. GND pin is from where all voltages are measured and it also completes an electrical circuit.

Input/Outputs pins

A GPIO pin that is set as an input pin, receives the incoming voltage signal sent by the device connected to this pin. A voltage between 1.8V and 3.3V will be read by the Raspberry Pi as HIGH and if the voltage is lower than 1.8V will be read as LOW.

Note: Do not give voltage more than 3.3V to GPIO pins, or else it will fry the Raspberry Pi zero.

A GPIO pin set as an output pin sends the voltage signal as high (3.3V) or low (0V). When this pin is set to HIGH, the voltage at the output is 3.3V and when set to LOW, the output voltage is 0V.

Other important pins

Along with the simple function of input and output pins, the GPIO pins can also perform a variety of alternative functions. Some specific pins are:

PWM (pulse-width modulation) pins

  • Software PWM available on all pins
  • Hardware PWM available on these pins: GPIO12, GPIO13, GPIO18, GPIO19

SPI pins

SPI (Serial Peripheral Interface) is another protocol used for master-slave communication. It is used by the Raspberry pi board to quickly communicate between one or more peripheral devices.

Data is synchronized using a clock (SCLK at GPIO11) from the master (RPi) and the data is sent from the Pi to our SPI device using the MOSI (Master Out Slave In) pin. If the SPI device needs to communicate back to Raspberry Pi, it sends the data back using the MISO (Master In Slave Out) pin.

  • SPI0: GPIO9 (MISO), GPIO10 (MOSI), GPIO11 (SCLK), GPIO8 (CE0), GPIO7 (CE1)
  • SPI1: GPIO19 (MISO), GPIO20 (MOSI), GPIO21 (SCLK), GPIO18 (CE0), GPIO17 (CE1), GPIO16 (CE2) 

I2C pins

I2C is used by the Raspberry Pi board to communicate with devices that are compatible with Inter-Integrated Circuit (a low-speed two-wire serial communication protocol). This communication standard requires master-slave roles between both devices.

I2C has two connections: SDA (Serial Data) and SCL (Serial Clock). They work by sending data to and using the SDA connection, and the speed of data transfer is controlled via the SCL pin.

  • Data: (GPIO2), Clock (GPIO3)
  • EEPROM Data: (GPIO0), EEPROM Clock (GPIO1)


Serial communication or the UART (Universal Asynchronous Receiver / Transmitter) pins provide a way to communicate between two microcontrollers or the computers. TX pin is used to transmit the serial data and RX pin is used to receive serial data coming from a different serial device.

  • TX (GPIO14)
  • RX (GPIO15)

Schematic (official):

To download the Raspberry Pi Zero schematic, click here.

Raspberry Pi Zero Schematic
Raspberry Pi Zero schematic

Different programming guide for R-Pi Zero (learning material):

You can control the GPIO of Raspberry Pi Zero using many programming languages. Some of the popular languages along with learning material is given below:

Prefer Book? Read this article on Best Raspberry Pi Books for beginners

Where to buy R-Pi Zero?

You don’t have to purchase RPI zero now as Zero W and Zero 2W (its updated versions) are now available. You can get the original Raspberry Pi Zero W board from different stores. But if you want to get it from Amazon, we recommend the following sellers:


Can Raspberry Pi Zero run Linux?

Yes, the Raspberry Pi Zero can run Linux.

How much RAM does Raspberry Pi Zero have?

It has 512MB LPDDR2 SDRAM.

Is Pi Zero 32 or 64-bit?

R-pi zero has an architecture width of 32-bit.

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Ankit Negi

I am an electrical engineer by profession who loves to tinker with electronic devices and gadgets and have been doing so for over six years now. During this period, I have made many projects and helped thousands of students through my blog and YouTube videos. I am active on Linkedin.

2 thoughts on “Guide to Raspberry Pi Zero GPIO Pinout & Specifications”

  1. Disappointed in this website – made me go out and buy a micro hdmi cable only to find out that the pi zero has a mini hdmi port! Please correct this mistake, annoying that this comes up first in google images.


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