Date & Time
Durations, ages, business days, and time zones.
17 calculators
Add or Subtract Days from a DateAdd or subtract days from a date to find a new date. Enter a start date and a number of days (negative to subtract). 90 days after 2026-01-01 is April 1, 2026.Age Calculator — years, months and daysCalculate your exact age in years, months and days from your date of birth, plus total days lived. Enter a birth date and an as-of date (defaults to today).Birthday Calculator — days until your next birthdayFind how many days until your next birthday, the age you'll turn, and its date. Enter your date of birth; it counts from today. Born June 15, you turn 36 in 106 days from Jan 1.Business Days Calculator — add or subtract working days from a dateFind the date a number of business days (Monday to Friday) after or before a start date. Weekends are skipped. 10 business days after January 1, 2026 is January 15, 2026.Business Days Calculator — count weekdays between datesCount the working days (Monday to Friday) between two dates, including both. Enter a start and end date to see business days, total calendar days and weekend days. January 2026 has 22 business days.Countdown Calculator — days until a dateCount down the days until any date. Enter a target date to see how many days (and weeks) remain from today. From 2026-01-01, Christmas is 358 days — 51 weeks and 1 day.Date Calculator — add or subtract years, months, daysAdd or subtract years, months, weeks and days from a date to find a new date. Enter a start date and an offset; use negatives to go back. 3 months and 2 weeks after Jan 1, 2026 is April 15.Date Midpoint Calculator — find the halfway dateFind the calendar date exactly halfway between two dates. Enter a start and end date to get the midpoint and the days on each side. Halfway through 2026 is July 2, 2026.Day of the Week Calculator — what day was a date?Find the day of the week for any date. Enter a date to see whether it falls on a Monday, Tuesday and so on, plus its day number in the year. 2026-08-06 is a Thursday.Days Between Dates CalculatorCount the number of days between two dates. Enter a start and end date for the exact day count, including across leap years. From 2026-01-01 to 2026-12-31 is 364 days.Leap Year Calculator — is it a leap year?Check whether any year is a leap year. A year is a leap year if divisible by 4, except centuries, which must be divisible by 400. 2024 is a leap year; 2026 is not; 1900 was not but 2000 was.Minutes to Hours ConverterConvert minutes to hours: hours = minutes ÷ 60. Get the decimal hours and the whole hours-and-minutes breakdown. 90 minutes is 1.5 hours, or 1 hour 30 minutes.Sleep Calculator — best bedtime for your wake-up timeFind what time to go to bed to wake up refreshed. Enter your wake-up time and the calculator counts back whole 90-minute sleep cycles. To wake at 7:00 AM, aim to be asleep by 11:30 PM for five cycles.Time Calculator — add or subtract hours and minutesAdd or subtract hours and minutes from a time of day. Enter a start time and an amount to get the resulting clock time, with a note when it lands on the next or previous day. 9:00 AM plus 5h 30m is 2:30 PM.Time Duration Calculator — hours between two timesFind how much time passes between a start and end time. Enter two clock times to get the duration in hours and minutes, decimal hours and total minutes. 9:00 to 17:00 is 8 hours.Time Zone Converter — convert times between citiesConvert a time from one city or time zone to another on any date, with daylight saving handled automatically. See the converted time, the day change, and the hours difference.Timesheet Calculator — work hours, overtime & payAdd up a week of clock-in / clock-out times to get total work hours, minus breaks, with overtime over 40 hours and optional gross pay.