What Day of the Week Was July 4, 2026?

The whole month, with July 4, 2026 highlighted and the US federal holidays marked. The column on the left is the US week number.

The years 1987, 1998, 2009, 2015, 2037, 2043, 2054, 2065 have the same calendar as 2026: they start on the same weekday and are common years too, so July 4 is a Saturday in each of them.

Zeller's congruence gives the weekday of any Gregorian date with a few sums:

1. Day q = 4; month m = 7.
2. Year of the century K = 26; century J = 20.
3. q + ⌊13 × (m + 1) ÷ 5⌋ + K + ⌊K ÷ 4⌋ + ⌊J ÷ 4⌋ + 5 × J = 4 + 20 + 26 + 6 + 5 + 100 = 161.
4. 161 divided by 7 leaves 0, and 0 stands for Saturday (0 is Saturday, 1 Sunday, up to 6 for Friday).

DateMath's calculator gets the same answer another way, by counting the days from a fixed date and taking the remainder after whole weeks.

DateMath counts the days from a fixed date to yours in the Gregorian calendar and takes the remainder after whole weeks, so every date in the years 1 to 9999 gets its weekday, leap days included. The same date is then numbered both ways: in the US, Sunday is day 1 of the week; in ISO 8601, Monday is day 1 and Sunday day 7. Today and tomorrow come from your device's date.

• The Gregorian calendar. DateMath treats every date as a Gregorian date, with its leap-year rule: a year divisible by 4 is a leap year, except century years not divisible by 400, so 2000 had a February 29 and 2100 will not. Source: Gregorian calendar.
• ISO 8601 week dates. DateMath numbers weeks by ISO 8601: weeks start on Monday, week 1 is the week with the year's first Thursday, and a year has 52 or 53 weeks. Source: ISO 8601.

DateMath's date math is tested against more than 100 cases worked out by hand. Every worked example and table on the site is computed with the same code the calculators run, so a page and its calculator can't disagree.