In this project, I’ll be showing you how you how to build an Arduino based reaction timer. The timer lights up a red LED and then measures how long it takes you to respond to the light by pushing a button. The time it takes to turn the LED on is randomised to eliminate guessing and the timer disregards the input if you hold the button down before the LED comes on. For a detailed write-up on the build and further description of the code & 3D print files, have a look at the full build through this link - https://www.the-diy-life.com/arduino-based-reaction-timer-improve-your-reaction-time/ Parts List and Purchase Links: Arduino Pro Micro - https://amzn.to/3bzgOr2 OLED Display - https://amzn.to/3aoOaYk Push Button - https://amzn.to/3culi2o LED - https://amzn.to/2KljoVT Resistors (220 ohm & 10K) - https://amzn.to/2VVBxz5 Ribbon Cable - https://amzn.to/3bbX78I Male Pin Header Strips - https://amzn.to/2VrQvML Female Pin Header Strips - https://amzn.to/3b9TO1N AA Battery Holder - https://amzn.to/3eClTkD Micro Slide Switch - https://amzn.to/3bmTrBf Cap Screws - https://amzn.to/2xLSgN5 For Testing: Breadboard & Jumpers - https://amzn.to/2S7rhTh Push Button (Only Used on Breadboard) - https://amzn.to/3eCjMgs 3D Printer Used - https://amzn.to/33MXHH0 Filament - https://amzn.to/2RBNwQJ If you’ve got any suggestions for Arduino projects or tutorials, let me know in the comments section below.