Day of Week Calculator : What Day of the Week Was It?
The Day of Week Calculator determines the precise day of the week (Sunday through Saturday) for any date across history. Discover what day of the week you were born on, verify historical events, or plan future meetings.
Interactive Calculator
100% Client-Side EngineStep-by-Step Examples
Moon Landing Date
Finding the weekday of the Apollo 11 Moon Landing on July 20, 1969.
July 20, 1969 occurred on a Sunday.
How to Use This Tool
- Choose any past, present, or future calendar date.
- Click Calculate to see the day of the week, ISO day index, weekend status, and ordinal day of year.
Frequently Asked Questions
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