LED Blinking on Arduino : Learn Arduino

LED Blinking on Arduino Uno should be your first Arduino project. Arduino Uno has an on-board or built-in LED, in this project we will see how to blink it.

Parts you will need:

  1. An Arduino Uno


  1. Connect Arduino with your computer.
  2. Download, install and open Arduino IDE. (See how)
  3. Within IDE chooose File Menu > Examples > 01. Basics > Blink
  4. Now click Verify button and wait for it finish the verification
  5. Finally click on Upload button, and you’re done!
  6. See the LED blinking!


  • Built-in LED is referenced by pin number 13.
  • In setup(), we declare this pin as output pin as we want to use it as so.
  • Next, in loop(), we turn it on, then wait for some time (delay) and than turn it off.
  • This process repeats infinitely.

Remember that this is your first Arduino project, do not worry much if you don’t understand every piece of it. If you are facing difficulties and need help, use comments section below.