DaysUntilNowCalendar tools
Not how far apart two dates are, but what the calendar says about a single one: which week it falls in, which weekday, which quarter, and how much of the year it leaves.
Day of the week calculator
Any date, past or future, and the weekday it lands on — plus the same date a year either side.
Leap year checker
Any year against all three parts of the rule, and which part decided the answer.
Quarter dates
Which quarter a date is in, on a calendar, federal or tax-year basis — and all four listed.
Week number today
Today's week in both numbering systems, with the dates the week runs between.
Working days in a year
Weekdays, holidays and hours for any year or month, with the leap-year surprise built in.
Year progress
The year as a percentage, plus the same bar for the quarter, the month and the week.
The calendar is not a measuring instrument. It is a set of rules that were argued over, legislated, and in places abandoned and restarted — and the awkward parts survive in exactly the places people need an answer: the week that belongs to last year, the year that skips its leap day, the month that holds four more working days than the one before it.
Which one answers your question
“What week are we in?” — week number today gives the ISO 8601 number and the US number side by side, plus the seven dates the week covers, because the two conventions disagree for most of the year and neither is labelled on the document that asked you.
“What day of the week was that?” — day of the week calculator names the weekday for any date from the 1500s onwards, with the day of the year, the week it sits in and the same date a year either side.
“Is that year a leap year?” — leap year checker runs all three parts of the 4/100/400 rule and says which part decided it, then lists the next five leap years and the weekday of February 29.
“How many working days does that leave?” — working days in a year counts weekdays for a year or a single month, takes off the US federal holidays if you want them off, and converts to hours at your own length of working day.
“How far through the year are we?” — year progress measures the elapsed share of the year, quarter, month or week as a bar and an exact figure, with the days and weeks still to come.
“When does the quarter start?” — quarter dates gives the boundaries on a calendar, US federal or UK tax basis, all four quarters at once, and how much of the current one has gone.
The two places a year refuses to be tidy
Seven does not divide 365. A year is 52 weeks plus a day or two, so weeks never line up with years and something has to give: ISO week 1 borrows days from December, the US convention accepts a one-day week, and every fixed date shuffles forward a weekday each year. The week number, weekday and working-day tools are all consequences of that single remainder.
The leap rule is an approximation that skips. Three of every four century years lose their leap day, which is why 1900 was 365 days and 2000 was 366. It has not mattered since 1900 and will not again until 2100, which is precisely why so much software has it wrong.
If your question is about the distance between two dates rather than the properties of one, that is the date calculators group. If it is about when a holiday falls and what happens when it lands on a weekend, that is holiday dates. And if you simply want to watch the time run down to something, the countdowns tick every second.
Frequently asked questions
Why do calendar answers differ between countries when the dates are the same?
Because the numbering conventions are national, not the calendar. The date is the same everywhere the Gregorian calendar is used; what changes is where a week is deemed to start, which week counts as the first of the year, which days are public holidays, and when the financial year begins. That is why a week number, a working-day count and a quarter label can each be right in one office and wrong in the next, while the underlying date is not in dispute at all.
Which of these tools do I need to check a deadline?
Start with the day of the week calculator, because a deadline that lands on a Saturday usually is not really the deadline. Then check working days if the period is counted in business days rather than calendar days, and quarter dates if the deadline is tied to a reporting period rather than to a date. The distance itself — how many days from now — belongs to the date calculators group instead.
Do these tools use my time zone or a server's?
Yours. Everything on this page is computed in the browser from your device’s own calendar date, so a week number or a percentage never turns over on somebody else’s midnight. The arithmetic itself is done on UTC midnights, which is what keeps whole-day counting from gaining or losing a day when the clocks change.
How we calculate this
Every tool in this group shares one date engine and one set of rules. Dates are held as UTC midnights and compared in whole days, so nothing gains or loses a day at a clock change. Leap years use the full Gregorian rule, including the century exception, for every year in range rather than only for the years where it makes no difference.
Week numbers are computed both ways from their own definitions: ISO 8601 through the Thursday rule, US numbering by counting Sundays from 1 January. Working days are Monday to Friday, with the eleven US federal holidays generated from their statutory rules and moved under the observance rule in 5 U.S.C. 6103; holidays elsewhere differ and each tool that uses them says so. Quarters are three whole months counted from whichever day the selected year begins on, so the day counts follow the real calendar rather than an assumed 91.
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