Dates & time
Date arithmetic that respects real calendars: leap years, business days, time zones and week numbers. 68 tools, including Add business days calculator, Add or subtract days from a date, Age calculator and Age in days calculator. All free, with no account and nothing to install.
What is today?The date, public holidays, international days, what happened on this day, famous birthdays, sunrise, sunset and the moon.See today →Add business days calculatorFind the date a number of working days after a start date (weekends skipped).Add or subtract days from a dateFind the date a number of days before or after a starting date.Age calculatorWork out your exact age in years, months and days from your birth date.Age in days calculatorConvert your age into total days, weeks and approximate years.Anniversary CalculatorHow long has it been, exactly? Years, months and days elapsed since a wedding, a first date, a friendship or a first day at work, the total in days, weeks and hours, the countdown to the next anniversary, the milestones coming up (10 000 days, silver, gold) and — for weddings — the traditional and modern gift for that year, in both the British and the American lists.Autumnal Equinox CalculatorGet the exact instant of the autumnal equinox and of all four seasonal markers for any year, in UTC and in your own offset, with northern and southern naming and the length of each astronomical season.Birth Day of the Week CalculatorFind the weekday you were born on, the weekday of your next birthdays, which weekdays repeat most, and the Doomsday rule behind it.Birthday across cultures calculatorThe same birth date gives three different ages: the Western count of completed birthdays, the Chinese 虚岁 (one at birth, +1 each Lunar New Year, using a 1900–2100 table), and the Korean traditional age. It also gives your Chinese and Western zodiac signs.Business days calculatorCount the working days (Monday–Friday) between two dates.Countdown calculatorCount down the days and weeks remaining until an event.Daily Time Savings CalculatorSee how a few minutes saved each day compound into hours, work days and weeks over a year.Date CalculatorAdd or subtract years, months, weeks and days from any date, with a business-day mode and explicit month-end clamping.Date difference calculatorCount the days, weeks and months between two dates.Date Pattern GeneratorList palindrome, repdigit, sequential and square-root dates over any year range, labelled per date format (DD/MM/YYYY, MM/DD/YYYY, YYYY-MM-DD).Day of the Year CalculatorThe ordinal day number of any date — the ISO 8601 ordinal format — with the days remaining, the ISO week, the quarter, the weekday, the percentage of the year elapsed, and the month-by-month addition shown in full.Day of Year CalendarA full year on one page: twelve month blocks where every cell carries its day-of-year number from 1 to 365 or 366, today highlighted, and each date's ISO week, quarter and days remaining one click away.Days in a Month CalculatorThe number of days in any month of any year from 1 to 9999, the leap rule worked through line by line for February, the weekday of the 1st and of the last day, how many of each weekday the month holds, and the calendar itself.Days until date calculatorCount the number of days from today until a future date.Email Reply Time CalculatorA tongue-in-cheek guide to the ideal window to reply to an email, from sender, urgency, timing and your strategy.First Day of Autumn CalculatorThe exact instant autumn begins — September equinox in the north, March equinox in the south — and how many minutes of daylight your latitude loses each day at that moment, the fastest rate of the year.First Day of Spring CalculatorThe exact instant spring begins in either hemisphere — March equinox in the north, September equinox in the south — in UTC and in your own offset, with the astronomical and meteorological start side by side and the next ten years.First Day of Summer CalculatorThe exact instant summer begins — June solstice in the north, December solstice in the south — plus the latitude above which the Sun never sets and why summer is the longest astronomical season.First Day of Winter CalculatorThe exact instant winter begins — December solstice in the north, June solstice in the south — why it is the shortest astronomical season, and why meteorological winter straddles two calendar years.Flight distance calculatorThe distance between two airports as the crow flies — the great-circle distance from the haversine formula — plus a realistic flight distance with a routing allowance and an estimated flight time from the aircraft's cruising speed. Enter IATA codes (JFK, CDG…), city names, or coordinates.Generation calculatorFind out which generation you belong to based on your birth year.Half Birthday CalculatorGet your half birthday two ways — six calendar months later and exactly half the days later — with a countdown from any reference date.Halfway Date CalculatorFind the exact midpoint between two dates and times, down to the leftover hours, plus quarter and third markers and the elapsed/remaining split.Hebrew calendar converterConvert any date between the Gregorian and Hebrew (Jewish) calendars, both ways and live as you type. It shows the Hebrew day, month name (Tishrei, Cheshvan, Av…) and year counted from Creation (Anno Mundi), correctly handling leap years where Adar splits into Adar I and Adar II. Powered by the exact Dershowitz–Reingold arithmetic algorithm.Hijri calendar converterConvert dates between the Gregorian and Islamic (Hijri) calendars in both directions, updating live as you type. It shows the Hijri day, month name (Muharram, Safar, Ramadan…) and the year counted from the Hijra (AH), using the tabular civil algorithm with the standard astronomical epoch. Note that arithmetic dates may differ by a day from the local moon-sighting calendar.How Long Ago CalculatorMeasure the time elapsed since any past date, live to the second, in years-months-days, weeks or plain days — and see what share of your life ago it was.How Long Until CalculatorA live countdown to any date and time — days, hours, minutes and seconds ticking every second, with the calendar breakdown and one-click presets.Is It April Fools' Day? CalculatorA straight yes or no, a live countdown to 1 April, the weekday it falls on for the next ten years and how the prank tradition differs from France to Iran.Is It Christmas? CalculatorA straight yes or no, a live countdown to 25 December, the weekday Christmas falls on for the next ten years and how many shopping days and Saturdays you have left.Julian Date converterConvert a calendar date and time to the astronomical Julian Date (JD) and back, live. It also returns the Modified Julian Date (MJD = JD − 2400000.5) and the Unix timestamp, and lets you pick the Gregorian or Julian calendar for dates before the 1582 reform. Astronomer-grade: noon UTC on 1 January 2000 comes out to exactly JD 2451545.0.Leap Year CalculatorCheck whether any year is a leap year with the /4, /100, /400 rule shown step by step, plus the previous and next leap years, the days left until 29 February and the Julian-calendar caveat before 1582.Leap Years List CalculatorList every leap year in the range you choose, with the count, the century exceptions highlighted (1700, 1800 and 1900 skipped; 1600 and 2000 kept) and a one-click copy of the whole list.Longest Day of the Year CalculatorHow long the longest day actually lasts at your latitude, how many minutes more daylight that is than at the equinox, the ten longest days of the year and the month-by-month curve — June solstice in the north, December in the south.Chinese lunar calendar converterConvert dates between the Gregorian solar calendar and the traditional Chinese lunisolar calendar (1900–2100), both ways and live. It shows the lunar month and day names, the sexagenary stem-branch (干支) year and its zodiac animal, and correctly handles leap months (闰月). Find out which lunar date a birthday falls on, or when Chinese New Year lands.Military Time ConverterConvert between 12-hour and 24-hour military time in both directions, with the full 0000-2300 chart, how to say each time out loud and the NATO zone letters.Next birthday countdownCount the days until your next birthday and the age you'll turn.Next Leap Year CalculatorThe next leap year after any year you enter, the twelve that follow, and the gap between each one — including the eight-year jump from 2096 to 2104 that most people never notice.Packing list generatorA tailored packing checklist for your trip — pick the trip type (beach, city, business, hiking, winter), the number of days and the climate, and it builds a categorised list with quantities that scale with the length of the stay. Tick items off as you pack; a carry-on-only mode trims the counts.Public holidays calendarEvery public holiday in 26 countries, for any year, computed from the rules rather than copied from a list: Easter and the eleven feasts that follow it, the nth-Monday holidays, the British substitute days and the Colombian Emiliani shift. Regional days included for Germany, Spain, France, the UK and Portugal.Reading time calculatorEstimate how long a text takes to read from its word count.Retirement age calculatorEstimate when you can retire based on your savings and contributions.School holidays calendarSchool holiday dates for France, Germany, Switzerland, Austria, Belgium, Luxembourg and Portugal, imported from the authorities that decree them — with the French academy picker that answers which zone you are in. Unlike public holidays these dates follow no rule, so the page shows when the snapshot was taken and how far it reaches, and names the countries where no single source exists.Screen time calculatorSee how much your daily screen time adds up to over a week and a year.Sentence reduction calculatorEstimate a release date from a sentence and its credits. Enter the start date and the full term, then the good-behavior credit (as a percentage of the sentence — day-for-day is 50%), any earned-time days from programs, and work credits. It subtracts them and projects the served time, the reduction and the estimated release date.Shortest Day of the Year CalculatorHow little daylight the shortest day leaves at your latitude, how many minutes less that is than at the equinox, polar night counted day by day, and the ten shortest days of the year — December solstice in the north, June in the south.Sick day believability calculatorThinking of pulling a sickie? This just-for-fun calculator weighs the day of the week, the weather, your excuse, your recent absences, how you deliver the news and what is happening today, then estimates how believable your sick-day call really is — with a verdict from Danger to Expert.Snow day calculatorWill school be cancelled tomorrow? Enter the forecast — temperature, snowfall, wind, snow already on the ground — plus your region, school type, road conditions and whether freezing rain is expected, and this heuristic calculator estimates the odds of a snow day.Speech time calculatorEstimate how long it takes to read a speech aloud from its word count.Statute of limitations calculatorWork out the filing deadline once you know your limitation period. Enter the date the clock starts — the incident, or the date you discovered the harm — and the number of years that applies, and it returns the deadline date and the time you have left. Typical US ranges: personal injury 1–3 yr, written contract 3–6 yr, but periods vary by state and change with the law, so enter the value for your jurisdiction.Summer Solstice CalculatorThe exact instant of the solstice plus the length of the longest day at your latitude, sunrise and sunset in solar time, midnight sun handled without error, and a day-by-day table showing why the Sun appears to stand still.Time converterConvert between s, min, h, day, week and more. Free time converter, instant and accurate.Time duration calculatorWork out how much time passes between a start and an end time.Time zone converterConvert a time from one UTC offset to another.Twitter/X Timestamp ConverterConvert a tweet URL or Snowflake ID to its exact posting time — and turn any date back into a Snowflake ID.Unix Time ConverterConvert a Unix timestamp (seconds or milliseconds) to a readable date and back, with the live current timestamp.Unix Timestamp ConverterConvert a Unix timestamp into a readable UTC date and time.Vernal Equinox CalculatorThe March equinox to the second for any year from 1 to 9999, all four seasonal markers, the Sun's declination at that instant, and the equilux — the date day and night really do last 12 hours each, which is not the equinox.Week number calculatorFind the ISO week number for any date of the year.Day of the week calculatorFind out which day of the week any date falls on.Weeks until calculatorCount how many weeks and days are left until a future date.When Is a Leap Year? CalculatorThe /4, /100, /400 rule stated in three plain lines, the date of the next 29 February with a live countdown, and the number of days February has for each of the next ten years.Winter Solstice CalculatorThe exact instant of the solstice, the length of the shortest day at your latitude, polar night handled properly, and the dates of the earliest sunset and latest sunrise — which fall weeks away from the solstice itself.World ClockSee the live local time and day/night in cities around the world, side by side. Add or remove any city.Zombie survival time calculatorWhen the outbreak hits, how long would you last? Choose your location, shelter, weapon, fitness, group and supplies, and this apocalyptic calculator estimates your survival time in days and weeks — and awards you a survivor rank, from zombie chow to wasteland legend.