Day of the Week Calculator
Discover what day of the week any calendar date was or will be.
Days of the week
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Select a date to see the day
How is the day of week determined?
The day of the week is calculated using mathematical algorithms that consider the Gregorian calendar, leap years, and historical adjustments.
Zeller's Algorithm
One of the best-known methods is Zeller's congruence, a mathematical formula that determines the day of the week for any date.
Applications
Useful for event planning, discovering what day historical dates fell on, or knowing what day an important future date will be.