No. 01beginner
LED Blink
The Hello World of Arduino. Blinks an external red LED on pin 13 on and off every second.
beginnerLEDdigital output
03 / Templates
ALL TEMPLATES
Ready-to-open Arduino projects with code, wiring diagrams, and component guides. Pick one and start learning.
No. 02beginner
LED Bar Graph
Knight Rider chaser on a 10-segment LED bar graph. A single lit dot sweeps forward and backward using pins 2–11.
beginnerLEDbar graph
No. 03intermediate
LED Ring Rainbow
16-pixel NeoPixel ring running a spinning rainbow chase via FastLED. Data driven from a single pin using the WS2812B protocol.
intermediateNeoPixelWS2812B
No. 04beginner
NeoPixel Colour Cycle
A single WS2812B NeoPixel cycling through red, green, blue, and yellow every 600 ms via Adafruit NeoPixel library.
beginnerNeoPixelWS2812B
No. 05intermediate
NeoPixel Matrix Rainbow
8×8 WS2812B NeoPixel matrix running a diagonal rainbow wave. Each pixel is addressed by row and column via Adafruit NeoPixel.
intermediateNeoPixelWS2812B
No. 06beginner
7-Segment Counter
Counts 0–9 on a single 7-segment display, updating once per second. Each segment A–G is driven directly from a digital pin. In real hardware, add a 220 Ω resistor in series with each segment pin.
beginner7-segmentdisplay
No. 07intermediate
LCD 1602 Hello World
Displays 'Hello, World!' on row 1 and a live uptime counter on row 2, using the LiquidCrystal library in 4-bit mode. Wire RW and V0 to GND in real hardware.
intermediateLCDdisplay
No. 08intermediate
ILI9341 TFT Display
240×320 colour TFT display over SPI. Draws a red rectangle, cyan circle, and white text using the Adafruit ILI9341 library. Runs on 3.3V logic — add level shifters on real 5V hardware.
intermediateTFTSPI
No. 09intermediate
LCD 2004 Four Rows
Writes a static message to all four rows of a 20×4 LCD using the LiquidCrystal library in 4-bit mode. Identical wiring to the 1602 — only lcd.begin() changes.
intermediateLCDdisplay
No. 10intermediate
SSD1306 OLED
128×64 monochrome OLED over I²C. Displays 'Hello!' and display info using the Adafruit SSD1306 library. Default I²C address is 0x3C.
intermediateOLEDI2C
No. 11beginner
Pushbutton Toggle LED
Press the button to toggle a red LED on and off. Uses INPUT_PULLUP so no external resistor is needed on the button — reads HIGH when released, LOW when pressed.
beginnerbuttonLED
No. 12beginner
Pushbutton 6mm Serial
Compact 6mm pushbutton that prints 'Button pressed!' to the Serial Monitor on each press. Uses INPUT_PULLUP — no external resistor needed.
beginnerbutton6mm
No. 13beginner
Slide Switch
SPDT slide switch wired between GND and 5V. The common pin reads LOW or HIGH depending on switch position. Click the switch on the canvas to toggle it — the Serial Monitor shows the state.
beginnerswitchdigital input
No. 14intermediate
Membrane Keypad
4×4 membrane keypad (16 keys: 0–9, A–D, *, #) wired to 8 Arduino pins via row/column scanning. Requires the Keypad library. Press a key and its character prints to the Serial Monitor.
intermediatekeypadinput
No. 15beginner
DIP Switch 8
Read all 8 switches of a DIP-8 package as a byte. Each closed switch pulls its Arduino pin LOW via INPUT_PULLUP. Flip switches on the canvas and watch the binary value update in the Serial Monitor.
beginnerswitchdigital input
No. 16beginner
Potentiometer
Read an analog value from a potentiometer and use it to fade an LED's brightness via PWM, while printing the raw and mapped values to the Serial Monitor.
beginneranalog inputPWM
No. 17beginner
Buzzer
Play tones and short melodies on a piezo buzzer using Arduino's tone() function — no resistor required.
beginnerbuzzertone
No. 18beginner
Servo Sweep
Read a potentiometer's position and use it to set a servo's angle in real time — a classic analog-input-to-motion demo.
beginnerservoanalog input
No. 19intermediate
DHT22 Monitor
Read temperature and humidity from a DHT22 sensor over its single-wire protocol and print both to the Serial Monitor every 2 seconds.
intermediatesensorserial
No. 20intermediate
HC-SR04 Distance Meter
Trigger an ultrasonic ping and measure the echo's round-trip time to compute distance, printed to the Serial Monitor.
intermediatesensorserial
No. 21intermediate
RGB LED Colour Fade
Drive all three channels of an RGB LED with PWM to mix colours and fade smoothly through the colour wheel.
intermediateRGB LEDPWM
No. 22beginner
Photoresistor Night Light
Read an ambient-light sensor and switch an LED on when it gets dark — a classic night-light circuit. The simulator drives the sensor with a slow day/night cycle since there's no physical light to shine on it.
beginnersensoranalog input
No. 23beginner
Analog Joystick
Read both axes of an analog joystick plus its built-in pushbutton, printing X/Y position and button state to the Serial Monitor.
beginnerjoystickanalog input
No. 24beginner
LED Blink (Nano)
The classic LED Blink, rebuilt on an Arduino Nano — a board-swap variant showing the Nano works exactly like the Uno since it's the same ATmega328p chip.
beginnerLEDdigital output
No. 25beginner
Slide Potentiometer
Read an analog value from a linear slide potentiometer and use it to fade an LED's brightness via PWM, while printing the raw and mapped values to the Serial Monitor.
beginneranalog inputPWM
No. 26beginner
Tilt Switch
Read a ball-and-tube tilt switch to detect orientation changes, printing the state to the Serial Monitor. The simulator alternates the switch on a timer since it has no clickable tilt control.
beginnerswitchdigital input