Date & Calendar Math

Day of the Week Calculator

Find the exact weekday (Monday-Sunday) for any historical, current, or future date.

Calculation Result

Instant
Tuesday
Date: 2026-09-29 (Day 272 of the year, ISO Week 40)
Day of Week
Tuesday
Weekend Day?
No
Zodiac Sign
Libra
Leap Year?
No

About Day of the Week Calculator

Discover the day of the week for birthdays, historical events, and upcoming milestones along with astrological and calendar trivia.

Calculation Methodology & Formula

Uses Zeller’s congruence and Gregorian calendar day mapping algorithms.

How to Use This Calculator

  1. Select or type any date.
  2. Click "Find Day of Week".
  3. View weekday name, day of year, week number, and zodiac sign.

Frequently Asked Questions

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