# How do you perform calendar calculations in your head?

**URL:** <https://boards.straightdope.com/t/how-do-you-perform-calendar-calculations-in-your-head/396970>\
**Category:** Factual Questions\
**Created:** [March 22, 2007, 2:36am UTC](https://boards.straightdope.com/t/how-do-you-perform-calendar-calculations-in-your-head/396970 "2007-03-22T02:36:41Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![alterego](https://avatars.discourse-cdn.com/v4/letter/a/6bbea6/32.png) [@alterego](https://boards.straightdope.com/u/alterego)\
**Post date:** [March 22, 2007, 2:36am UTC](https://boards.straightdope.com/t/how-do-you-perform-calendar-calculations-in-your-head/396970/1 "2007-03-22T02:36:41Z")

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If someone tells you an arbitrary date, e.g., April 24, 1734, how do you tell them the day of the week? Assume I’m willing to practice complicated calculations until I master them.

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**Author:** ![Cunctator](https://avatars.discourse-cdn.com/v4/letter/c/43a26b/32.png) [@Cunctator](https://boards.straightdope.com/u/Cunctator)\
**Post date:** [March 22, 2007, 3:22am UTC](https://boards.straightdope.com/t/how-do-you-perform-calendar-calculations-in-your-head/396970/2 "2007-03-22T03:22:48Z")

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There are [many algorithms](http://en.wikipedia.org/wiki/Calculating_the_day_of_the_week) that you could use.