Pinouts
A tap-able pin diagram for every board, what each pin does, and the gotchas that stop beginner projects.
ESP32 DevKit V1
3.3 V logic — NOT 5 V tolerant
ESP32-S3
3.3 V logic — NOT 5 V tolerant
Arduino Uno R3
5 V logic
Arduino Nano
5 V logic
NodeMCU ESP8266
3.3 V logic
ESP32-C3 SuperMini
3.3 V logic — NOT 5 V tolerant
Raspberry Pi Pico / Pico W
3.3 V logic — NOT 5 V tolerant
Raspberry Pi 40-pin GPIO
3.3 V logic — NOT 5 V tolerant, no analog inputs
Designer
LED Matrix Designer
Draw on the 12×8 LED matrix with your mouse or finger, pick a preset or invert it, then copy a ready-to-upload Arduino sketch.
Open the designerCalculators
Ohm's Law
Voltage, current, resistance and power.
LED Resistor
Series resistor, standard value and color bands.
Resistor Color Code
Decode 4 and 5 band resistors.
Capacitor Code
104 = 100 nF, plus RC timing.
Voltage Divider
Vout, or solve for R1 (5 V to 3.3 V).
Battery Life
Runtime, incl. ESP32 deep sleep.
ADC to Voltage
Raw analogRead() to volts.
Servo & PCA9685
Angle to pulse, PCA9685 ticks, power.
Educational use only. All tools are provided "as is" without warranty. Always check your part's datasheet. See the full disclaimer.