Today is Wednesday, Wednesday, September 30, 2026. Tomorrow is Thursday, and 100 days from now is Friday, January 8, 2027. Enter any date to find its weekday, or open a ready-made page for a calendar date such as January 1.
The weekday of any date follows from the count of days since a known reference date, taken modulo seven. The calculator applies that rule to real calendar dates, including leap days, so it works for the past and the future alike.
Birthdays, anniversaries, deadlines and event dates are easier to plan once you know the weekday. Historians, genealogists and lawyers also need to know whether a date fell on a weekend or a weekday.
Each result page shows the day of the year, the ISO week number, the quarter and the weekday of the same date over the next few years.
Today is Wednesday, September 30, 2026. That is day 273 of 365 in 2026, in ISO week 40, with 92 days to go before the year ends. The next dates people plan around are Diwali on Saturday, October 10; Columbus Day on Monday, October 12; Halloween on Saturday, October 31. The moon is a Waning Gibbous tonight, with about 81% of its face lit. All of these figures are recalculated when the page loads, so they always describe the day you open it, not the day the page was published.
The Gregorian calendar has twelve months of 28 to 31 days. A normal year has 365 days and a leap year has 366, with the extra day added to February in every year divisible by four except century years that are not divisible by 400. Because 365 is one more than 52 weeks, most dates move forward one weekday each year and two after a leap day. Weeks are numbered under ISO 8601, which starts weeks on Monday and gives week 1 to the week containing the first Thursday of January.
When you count days for a deadline, decide first whether the start day and the end day are included, because the answer changes by one. For work, subtract weekends and public holidays from calendar days to get business days. For anything that crosses a daylight-saving change, use elapsed hours instead of a fixed twenty-four hours a day. If a date matters legally or financially, confirm it against the source document or the official announcement before you rely on any online calculator.
Enter the date in the box above and the calculator shows the weekday.
Yes, any date from 1900 to 2200 works.
Yes.
The result page shows how many days into the year the date falls.
The result page shows the ISO-8601 week, which starts on Monday.
Today is Wednesday.
Yes, use the month-and-day pages in the list below.
The Gregorian calendar.
Yes.
Only for today's date, which follows this site's time zone, -04:00.