Date & Time Calculators
Age, date differences, durations and deadlines.
Age CalculatorCalculate exact age between two dates in years, months and days, plus total months, weeks and days. Works for birthdays, anniversaries and document deadlines.Business Days CalculatorCount the Monday-to-Friday business days between two dates, including or excluding the end date. Public holidays are not subtracted automatically.Conception Date CalculatorEstimate a likely conception date and window from a due date or a birth date, using the standard 266-day conception-to-birth convention.Date Calculator (Add or Subtract)Add or subtract days, weeks, months or years from any date and get the resulting weekday and full date, with correct month-end clamping.Date Difference CalculatorFind the exact difference between two dates in years, months and days, plus totals in days, weeks and months. Works with dates entered in either order.Day of the Week CalculatorFind the day of the week for any date, past or future, plus its day-of-year number, days in that year, and whether it is a leap year.Days Until CalculatorCalculate how many days, weeks and days remain until any target date, or how many days have passed if that date is already behind you.Pregnancy Due Date CalculatorEstimate your pregnancy due date from your last period and cycle length using Naegele's rule, plus your current gestational week and trimester.Leap Year CalculatorCheck if any year is a leap year under the Gregorian rule, see why, how many days it has, Feb 29's weekday, and the 5 leap years before and after it.Moon Phase CalculatorFind the moon phase and illumination percent for any date using the mean synodic month, plus days since or until the next new and full moon.Next Birthday CalculatorFind days until your next birthday, the weekday it falls on, the age you'll be turning, and a table of your next 5 birthdays with weekdays.Ovulation CalculatorEstimate ovulation day and your fertile window from your last period and cycle length, with a table projecting the next 3 cycles. Not a contraceptive method.Period CalculatorPredict your next period and the following 5 cycles from your last period, cycle length and period length, shown as a start/end date table.Pregnancy Week CalculatorFind your current pregnancy week and trimester from your last period or due date, plus weeks remaining and a trimester-boundaries reference table.Time Duration CalculatorCalculate the duration between two clock times in hours and minutes, decimal hours and total minutes. Automatically handles shifts that cross midnight.Time Zone ConverterConvert a date and time between 25 major time zones using fixed standard UTC offsets. Clearly states that daylight saving time is not applied.Unix Timestamp ConverterConvert a Unix timestamp (seconds or milliseconds, auto-detected) to a UTC date and time, or a date and time to a timestamp. Shows ISO 8601 too.Week Number CalculatorFind the ISO 8601 week number and week-year for any date. Correctly handles year-boundary weeks, like December 30, 2024 falling in week 1 of 2025.Work Hours CalculatorCalculate hours worked per shift after unpaid breaks, your weekly total across your work days, and daily or weekly pay at your hourly rate.Zodiac Sign CalculatorEnter a birth date to get your Western zodiac sign, its element and neighbouring signs, plus your Chinese zodiac animal. For entertainment purposes only.