ESP32-C3

Small, cheap, RISC-V. One core that does one thing at a time, and does it well.

Before you plan anything

Single core, no touch pins, no DAC.

A long blocking loop now delays Wi-Fi housekeeping, because there is no second core to carry it. Keep loop() short.

Wi-Fi 4BLE 5No classic BTNo Zigbee or ThreadUSB serial/JTAGNo DACNo touch pinsNo PSRAMSingle coreNo MIPI display

RISC-V · 1 × 160 MHz

ESP32-C3 board photo

We stock

ESP32-C3 SuperMini

Thumbnail sized and the cheapest way to get something on Wi-Fi. Watch GPIO8 — it is the on-board LED.

See it in the shop →

The pins that matter

Not all forty-odd of them. The five rows that decide whether your wiring works.

Default I2CSDA 8 · SCL 9Core default — but see the warning below about GPIO 8.

On-board LEDGPIO 8On the SuperMini. It shares a pin with the I2C default and has a pull-up on it.

We use insteadSDA 5 · SCL 6Our board profile moves I2C off GPIO 8 for exactly that reason.

Strapping pinsGPIO 2, 8, 9GPIO 9 is the BOOT button. Pulling GPIO 2 low at boot stops it starting.

ADC pinsGPIO 0–4Five analog inputs, all on ADC1, so Wi-Fi does not interfere.

Pinout diagram — ESP32-C3 SuperMini

Board settings, all three toolchains

Get one of these wrong and nothing else on the site will work.

Arduino IDEC++Tools → BoardESP32C3 Dev Module

On the SuperMini set "USB CDC On Boot" to Enabled or Serial stays silent.

MicroPythonPython + ThonnyfirmwareESP32_GENERIC_C3-20260201-v1.25.bin

The REPL comes up on the native USB port with no extra driver.

PlatformIObuild systemplatformio.iniboard = esp32-c3-devkitm-1

Works for the SuperMini too; only the LED pin differs.

What catches people out on this chip

These are the support emails. They exist nowhere else on the site because they are true of nothing else.

GPIO 8 is the LED and the I2C default

Wire an I2C module to the core defaults on a SuperMini and the LED’s pull-up fights the bus. Move to GPIO 5 and 6 and it works immediately.

One core means Wi-Fi shares your loop

A delay(2000) in loop() is two seconds during which nothing services the radio. Long tasks need to be broken up.

No touch and no DAC

Two whole categories of tutorial simply do not apply. The site greys them out rather than letting you find out the hard way.

Resetting drops the serial port

USB serial/JTAG is part of the chip, so the port goes away on reset. Serial monitors that do not reconnect will look dead.

News about this chip

2026-09-02Arduino core 3.1 changes analogWrite resolution on the C3Sketches written against 3.0 now output 8-bit instead of 10-bit unless you set it explicitly. One line to fix.

2026-08-01MicroPython 1.25 firmware for all five chipsFresh .bin files, and the C6 build finally exposes the Wi-Fi 6 flags.

Guides for this chip

72 of 81 apply

Written once for the whole family. Opening one from here fixes the pins to this chip and the code to your language.

01 · Start hereWhat the ESP32 is 02 · Start hereChoosing your tools 03 · Setup and uploadingInstall the toolchain 04 · Setup and uploadingHello world over serial 05 · Setup and uploadingBlink an LED 06 · Setup and uploadingWhen uploads fail 07 · Setup and uploadingSerial ports and drivers 08 · Setup and uploadingPrinting, plotting and debugging 09 · The board itselfThe EN and BOOT buttons 10 · The board itselfThe pins you cannot use 11 · The board itselfWhat the chip says about itself 12 · Pins and signalsDigital I/O 13 · Pins and signalsPWM with LEDC 14 · Pins and signalsReading the ADC 15 · Pins and signalsuse insteadDAC output 16 · Pins and signalsuse insteadTouch pins 17 · Interrupts and timingInterrupts on a pin 18 · Interrupts and timingSharing data with an ISR 19 · Interrupts and timingHardware timers 20 · Interrupts and timingCounting pulses 21 · Interrupts and timingAddressable LEDs with RMT 22 · Wires on the boardDigital in and digital out 23 · Wires on the boardOne-wire sensor timing 24 · Wires on the board1-Wire and device chains 25 · Wires on the boardI2C, start to stop 26 · Wires on the boardI2C addresses and conflicts 27 · Wires on the boardI2C on a shared bus 28 · Wires on the boardSPI and chip select 29 · Wires on the boardUART, start to stop 30 · Wires on the boardIR remote codes 31 · BusesI2C 32 · BusesSPI 33 · BusesUART and baud rates 34 · BusesRS485 and Modbus 35 · StorageFilesystem on flash 36 · StorageUploading files to LittleFS 37 · StoragePreferences and NVS 38 · StoragemicroSD cards 39 · StoragePartition tables and flash size 40 · Joining a networkWi-Fi station mode 41 · Joining a networkAccess point mode 42 · Joining a networkBoth at once: AP and station 43 · Joining a networkSeveral networks, one board 44 · Joining a networkWi-Fi provisioning 45 · Joining a networkuse insteadWi-Fi 6 features 46 · Living on a networkmDNS and NTP 47 · Living on a networkKeeping time with time.h 48 · Living on a networkHTTPS and certificates 49 · Living on a networkOTA updates 50 · Living on a networkEthernet instead of Wi-Fi 51 · Web serverHello world from the board 52 · Web serverA reading on the page 53 · Web serverSwitching a pin from the page 54 · Web serverAsync web server 55 · Messages on the networkHTTP from a board 56 · Messages on the networkMQTT and a broker 57 · Messages on the networkWebSocket dashboards 58 · Messages on the networkNames and time 59 · Messages on the networkFirmware in two slots 60 · BluetoothBLE server and client 61 · BluetoothA value a phone can read 62 · BluetoothA value a phone can write 63 · Bluetoothuse insteadClassic Bluetooth serial 64 · Other radiosESP-NOW 65 · Other radiosESP-WIFI-MESH 66 · Other radiosuse insteadZigbee, Thread and Matter 67 · Other radiosLoRa for long range 68 · Sleep and wake-upDeep sleep and wake sources 69 · Sleep and wake-upHibernation, the floor below sleep 70 · Sleep and wake-upWaking on a timer 71 · Sleep and wake-upWaking on a pin or a touch 72 · Sleep and wake-upWhat survives deep sleep 73 · Sleep and wake-upuse insteadThe ULP low-power core 74 · PowerPower and the 3V3 rail 75 · PowerBattery and power budget 76 · PowerMeasuring current draw 77 · Systemuse insteadDual core tasks 78 · SystemCrash dumps and the watchdog 79 · SystemI2S audio 80 · Systemuse insteadCamera capture 81 · Systemuse insteadMIPI displays

Modules that work with the ESP32-C3

All modules work electrically. Touch-based and DAC-based lessons are marked as not applicable, and analog modules should stay on GPIO 0 to 4.

Browse the module index →