How to Find the Day of the Week for Any Date

The seven-day week repeats without gaps on the Gregorian calendar this site uses. The day of week calculator names Sunday through Saturday for a civil date from January 1, 1900 through December 31, 2100. It does not assign luck, astrology, or predictions to those names.

The seven-day week

After Saturday comes Sunday. After 7 elapsed days the weekday repeats. After 14 it repeats again. Leap days insert an extra date in February, which shifts later weekdays by one compared with a common year. That is the only February surprise in this model. The site does not reconstruct Julian calendar weekdays, proleptic schemes before 1900, or timezone-specific “start of day” stories.

Selecting a calendar date

Use the native date control, or Today, Tomorrow, and Yesterday, which are computed from the visitor’s local calendar date when clicked. Choose Another Date focuses the field so you can pick a different value. Invalid or out-of-range dates are explained instead of guessed.

How weekdays repeat

Worked example 1: January 1, 2000 is Saturday. January 8, 2000 is also Saturday. January 2, 2000 is Sunday. You can step with the add-days tool by 7 and watch the weekday finder stay put. Worked example 2: February 29, 2024 is Thursday. March 1, 2024 is Friday. In 2025, March 1 is Saturday, because 2025 has no leap day to insert between February 28 and March 1.

Why month lengths matter

A 31-day month that begins on Wednesday ends on Friday. A 30-day month that begins on Wednesday ends on Thursday. You cannot memorize “the 15th is always a Monday” across months. The miniature month grid on the finder highlights the selected day so you can see neighbors.

Leap years

Gregorian leap years follow the usual rule: divisible by 4, except centuries unless divisible by 400. 1900 is not a leap year; 2000 is; 2024 is; 2100 is not. Day-of-year for March 1 is 61 in a leap year and 60 in a common year. The finder prints that day number and a leap/common label.

Historical and future dates in range

January 1, 2025 is Wednesday. January 1, 2026 is Thursday. Those checks are in the finder page so you can verify the implementation. Dates before 1900 and after 2100 are out of scope. This article does not claim weekday names for earlier historical calendars.

Planning with a weekday

If you need a meeting on a Wednesday, find the weekday of a candidate date, then add 1–6 calendar days until Wednesday appears—or add business days if you only move Monday–Friday. The finder will not skip holidays. Combine it with the difference calculator when you also need a duration.

Daylight saving time

Weekdays are properties of civil dates, not of local clocks. A region that springs forward at 2:00 a.m. still has a Sunday on that date. Calendar arithmetic on this site uses UTC ordinals so a DST transition cannot change which weekday a YYYY-MM-DD value maps to. If a program subtracts local midnights, it can mis-count days across that night and then mis-label weekdays; Datefold Studio is written to avoid that class of bug. See also calendar rules.

The month grid on the finder can start the row on Sunday or Monday if you change that preference on the main calendar. The weekday name of a given date does not change when the header row shifts. Only the visual alignment changes. That is the same rule as the range calendar on the date difference page.

Related: days between dates.

Questions

Is January 1, 2000 really Saturday?

Yes, on the Gregorian calendar used here. Enter it on the finder to confirm.

Do you compute ancient Julian dates?

No. Only Gregorian civil dates from 1900 through 2100.

Why does Today use my local date?

Initial “today” should match the date on your wall calendar. Calculations between two typed dates stay timezone-independent.