Day of Week Calculator
Find out what day of the week any date falls on. Calculate for past, present, or future dates, including historical events and special occasions.
Step 1: Enter Date
About Calendar Systems
This calculator uses the Gregorian calendar, which was introduced in 1582. Dates before October 15, 1582, follow the Julian calendar, but this calculator adjusts for historical accuracy.
Step 2: Options
Fun Fact
The day of the week for any date can be calculated using mathematical formulas. One popular method is Zeller’s Congruence, invented by Christian Zeller in 1883.
Day of Week Results
The selected date falls on
Monthly Calendar View
Historical Events on This Date
| Year | Event | Day of Week |
|---|
Day of Week Calculation
Zeller’s Congruence Formula
h = (q + ⌊(13(m+1))/5⌋ + K + ⌊K/4⌋ + ⌊J/4⌋ – 2J) mod 7
Where h is day of week (0=Saturday, 1=Sunday, …, 6=Friday), q is day of month, m is month, K is year of century, J is zero-based century.
Need Professional Date Analysis?
Connect with our calendar experts for historical date verification, event planning, and scheduling optimization for your business or personal needs.
Get Professional Analysis