Day of the Week Game
In 2023 I saw a video of a person who could figure out the day of the week of any date in history all in their head. After some research I discovered it is just a clever math trick so I coded this website on GitHub to practice.
It has a live leaderboard (stored in Firebase) that ranks based on the number of correct guesses in a row and time per guess. The following leaderboard reflects the names of many people I saw in the news while creating and testing the site (i.e. NBA Finals 2025).
I made 85% of randomly generated dates after 1970, because most people only know the day they were born on and will ask you about that. After an incorrect guess, pressing the “Why?” button will explain the method I use to find the day of the week. There are other more intuitive ways but this is by far the quickest. For more info please read this paper on the “odd + 11” method.
Game link – https://trevorkates.github.io/date-game/
