ESP32-WROOM-32 Pinout (module)

ESP32-WROOM-32 is an Espressif module with the original ESP32 chip, flash memory, a crystal and an antenna under a shielding can. You will find it on ESP32 DevKit boards and in lots of finished devices, and when you design your own board, you solder it directly onto it.

The pinout applies to the WROOM-32, -32D and -32E variants as well as the -32U/-32UE versions with a connector for an external antenna.

Specifications

ESP32: 2× Xtensa LX6 up to 240 MHz, 520 kB SRAM
4 MB flash (8 and 16 MB on -32E as well, R2 versions with 2 MB PSRAM)
Wi-Fi 4 (2.4 GHz) and Bluetooth 4.2 (Classic and LE)
38 pads with 1.27 mm pitch, 26 usable GPIO
16 analog inputs (ADC1 + ADC2), 2× DAC, 10 touch inputs
3.0–3.6 V supply
18 × 25.5 × 3.1 mm (U/UE versions 18 × 19.2 mm)

For your own board, you need at least a 3.3 V regulator (500 mA or more), a pull-up with a capacitor on EN, and a button or jumper on GPIO0 for uploading. It is programmed via UART0 (GPIO1/GPIO3) with a USB-UART converter. On the -32 and -32D, pads 17–22 are connected to the flash memory; on the -32E they are not connected.

Pinout and pin table

Hover over a pin in the diagram or a table row; use the filter to highlight a bus. You can download the pinout as PNG or SVG.

Download:PNG SVG

License: CC BY 4.0 · How to credit

Pin table – ESP32-WROOM-32 (modul)
Pin	Name	Direction	UART	I2C	SPI	ADC	DAC	Touch	Note
1	GND	–
2	3V3	input							Power 3.0–3.6 V. Wi-Fi peaks above 300 mA when transmitting – size the regulator and capacitors for at least 500 mA.
3	EN	input							Chip enable (CHIP_PU): logic 1 = running, logic 0 = reset. Connect a 10 kΩ pull-up to 3.3 V and a 1 µF capacitor to GND (delayed start), or a button to GND.
4	GPIO36	input				ADC1_CH0			SENSOR_VP – input only, no internal pull-up/pull-down
5	GPIO39	input				ADC1_CH3			SENSOR_VN – input only, no internal pull-up/pull-down
6	GPIO34	input				ADC1_CH6			Input only, no internal pull-up/pull-down
7	GPIO35	input				ADC1_CH7			Input only, no internal pull-up/pull-down
8	GPIO32	input/output				ADC1_CH4		T9
9	GPIO33	input/output				ADC1_CH5		T8
10	GPIO25	input/output	TX2			ADC2_CH8	DAC1		DAC1 (8-bit); UART2 TX (Serial2, default in Arduino 3.x). ADC2 cannot be used with Wi-Fi on
11	GPIO26	input/output	RX1			ADC2_CH9	DAC2		DAC2 (8-bit); UART1 RX (Serial1, default in Arduino 3.x). ADC2 cannot be used with Wi-Fi on
12	GPIO27	input/output	TX1			ADC2_CH7		T7	UART1 TX (Serial1, default in Arduino 3.x). ADC2 cannot be used with Wi-Fi enabled
13	GPIO14	input/output				ADC2_CH6		T6	JTAG MTMS; ADC2 cannot be used with Wi-Fi on
14	GPIO12	input/output				ADC2_CH5		T5	Strapping pin (MTDI) – selects the flash voltage. The module has 3.3 V flash, so it must be logic 0 at power-up (internal pull-down), otherwise it will not boot. This can be fixed permanently with an eFuse (espefuse set-flash-voltage 3.3V). ADC2 cannot be used with Wi-Fi on.
15	GND	–
16	GPIO13	input/output				ADC2_CH4		T4	JTAG MTCK; ADC2 cannot be used with Wi-Fi on
17	GPIO9	input/output							Connected to flash memory (SD2) – do not use; not connected on -32E
18	GPIO10	input/output							Connected to flash memory (SD3) – do not use; not connected on -32E
19	GPIO11	input/output							Connected to flash memory (CMD) – do not use; not connected on -32E
20	GPIO6	input/output							Connected to flash memory (CLK) – do not use; not connected on -32E
21	GPIO7	input/output							Connected to flash memory (SD0) – do not use; not connected on -32E
22	GPIO8	input/output							Connected to flash memory (SD1) – do not use; not connected on -32E
23	GPIO15	input/output				ADC2_CH3		T3	Strapping pin – logic 0 at boot disables bootloader output. JTAG MTDO
24	GPIO2	input/output				ADC2_CH2		T2	Strapping pin – must be logic 0 or unconnected at boot for download mode
25	GPIO0	input/output				ADC2_CH1		T1	Strapping pin – logic 0 at boot (together with GPIO2 at logic 0) = UART download mode. For normal boot use a pull-up (internal is enough); boards have a BOOT button to GND.
26	GPIO4	input/output	RX2			ADC2_CH0		T0	UART2 RX (Serial2, default in Arduino 3.x). ADC2 cannot be used with Wi-Fi enabled
27	GPIO16	input/output							In use on PSRAM versions (-32E…R2); Serial2 defaults to GPIO4/25 in Arduino 3.x
28	GPIO17	input/output							Formerly the default UART2 TX; in Arduino 3.x, Serial2 defaults to GPIO4/25
29	GPIO5	input/output			SS				Strapping pin (SDIO timing) – logic 1 at boot (internal pull-up)
30	GPIO18	input/output			SCK
31	GPIO19	input/output			MISO
32	NC	–
33	GPIO21	input/output		SDA
34	GPIO3	input/output	RX						UART0 RX – firmware upload
35	GPIO1	input/output	TX						UART0 TX – firmware upload and log output
36	GPIO22	input/output		SCL
37	GPIO23	input/output			MOSI
38	GND	–
pad	GND	–

What to watch out for

The GPIO are not 5V tolerant.
GPIO12 must be at logic 0 at power-up – otherwise the flash gets 1.8 V and the module won’t start.
GPIO0 at logic 0 at boot switches to download mode; GPIO2 must be at logic 0 or unconnected during uploading.
GPIO34–39 are input-only with no internal pull-ups.
ADC2 (GPIO0, 2, 4, 12–15, 25–27) cannot be used while Wi-Fi is on.
There must be no copper or components under the antenna – place the module with the antenna over the board edge.

ESP32 on chiptron.eu/

Projects and guides on chiptron.eu/:

ESP32 chip comparison – when the original ESP32 is enough and when to choose the S3, C3 or C6
ESP32 and the FireBeetle board – the ESP32-WROOM-32 module with Li-ion charging in practice
YoRadio – internet radio with an ESP32 WROOM and an I2S DAC, Home Assistant support