ESP32 Pinout Guide: Understanding the Essential Connections

The ESP32 microcontroller is a powerful tool in the world of IoT, embedded systems, and robotics, offering a wide range of functionalities. In this guide, we’ll break down the ESP32 pinout, explaining the purpose of each pin and how you can use them effectively in your projects.

Pinout Diagram

Power Pins
GND 1 P Ground
3V3 2 P Power supply
EN 3 I Module-enable signal. Active high.

ADC
The Analog-to-Digital Converter (ADC) pins are used to read analog signals from sensors. The ESP32 has 15 ADC pins with a resolution of 12 bits, allowing it to read values ranging from 0 to 4095.
ADC1_CH0 (GPIO36)
ADC1_CH3 (GPIO39)
ADC1_CH4 (GPIO32)
ADC1_CH5 (GPIO33)
ADC1_CH6 (GPIO34)
ADC1_CH7 (GPIO35)

ADC2_CH0 (GPIO4)
ADC2_CH2 (GPIO2)
ADC2_CH3 (GPIO15)
ADC2_CH4 (GPIO13)
ADC2_CH5 (GPIO12)
ADC2_CH6 (GPIO14)
ADC2_CH7 (GPIO27)
ADC2_CH8 (GPIO25)
ADC2_CH9 (GPIO26)

DAC
DAC1 (GPIO25)
DAC2 (GPIO26)

RTC GPIOs
RTC_GPIO0 (GPIO36)
RTC_GPIO3 (GPIO39)
RTC_GPIO4 (GPIO34)
RTC_GPIO5 (GPIO35)
RTC_GPIO6 (GPIO25)
RTC_GPIO7 (GPIO26)
RTC_GPIO8 (GPIO33)
RTC_GPIO9 (GPIO32)
RTC_GPIO10 (GPIO4)
RTC_GPIO12 (GPIO2)
RTC_GPIO13 (GPIO15)
RTC_GPIO14 (GPIO13)
RTC_GPIO15 (GPIO12)
RTC_GPIO16 (GPIO14)
RTC_GPIO17 (GPIO27)

Input Only
GPIO34
GPIO35
GPIO36
GPIO39

SPI

I2C
SDA (GPIO21)
SCL (GPIO22)

Capacitive Touch

PWM Pins

Interrupt Pins