Day of Week Calculator

Find what day of the week any date falls on.

Date

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Guides & Reference

How It Works

Determines day of week for any date using Tomohiko Sakamoto algorithm. Works for all Gregorian calendar dates after October 15, 1582.

Formula

Zeller congruence

Common calculations — results you can verify instantly.

Jan 1, 2024

Using algorithm

Monday

July 4, 2024

Independence Day

Thursday

Dec 25, 2024

Christmas 2024

Wednesday

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Calendar repeats every 400 years exactly.

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Days change at midnight.

Using for dates before 1582

Before 1582 Julian calendar was used with different calculations.

Forgetting midnight day change

Events just before midnight use previous calendar day.

Saturday.

Tuesday.

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