Free Day of the Week Calculator

Useful for quickly checking what day a historical event fell on, or confirming what day of the week a future date (like a birthday or anniversary) will land on years out.

Worked Example

Example: July 4, 1776 fell on a Thursday. January 1, 2030 will fall on a Tuesday.

Formula / Method

Uses JavaScript's native Date.getDay(), which correctly implements the proleptic Gregorian calendar for any date, including historical and far-future dates.

Worked Example

Example: July 4, 1776 fell on a Thursday. January 1, 2030 will fall on a Tuesday.

Formula / Method

Uses JavaScript's native Date.getDay(), which correctly implements the proleptic Gregorian calendar for any date, including historical and far-future dates.