Toolsloft

Date & Time Tools

40 free tools, grouped by topic.

Age

  • Age CalculatorCalculate age in years, months, and days from a date of birth, plus total months, weeks, and days lived. Free and runs in your browser.
  • Age Difference CalculatorFind the difference between two dates in years, months, and days. Enter two birthdays in any order for the exact age gap.
  • Age in Days CalculatorFind your age in days, weeks, hours, and minutes from a date of birth. Exact calendar-day counting, right in your browser.
  • Age in Months CalculatorFind an age in total whole months plus leftover days from a birth date to any reference date.

Date math

  • Add Days to Date CalculatorAdd a number of days to any date and get the resulting date and weekday, with month lengths and leap years handled.
  • Add Hours to Time CalculatorAdd or subtract hours from a time of day, with the result shown in 24-hour and 12-hour format and a note when it crosses midnight into the next or previous day.
  • Add Minutes to Time CalculatorAdd or subtract minutes from a time of day, with the result in 24-hour and 12-hour format and a note when it crosses midnight into the next or previous day.
  • Add Months to Date CalculatorAdd a number of months to any date and get the resulting date and weekday, with short months handled.
  • Add Weeks to Date CalculatorAdd a number of weeks to any date and get the resulting date and weekday.
  • Add Years to Date CalculatorAdd a number of years to any date and get the resulting date and weekday, with leap-day handling.
  • Business Days CalculatorCount business days between two dates, skipping weekends and holidays you list. Get workdays, weekend days, and the total span.
  • Date Calculator (Add or Subtract)Add or subtract years, months, weeks, and days from a date to find a new date and its day of the week.
  • Date Difference CalculatorFind the difference between two dates in years, months, days, weeks, and total days. Order does not matter and it runs in your browser.
  • Days Between DatesCount the number of days between two dates, including business days and weekend days, with an option to include the end date.
  • Days Since Date CalculatorCount the days since a past date, with the elapsed time also shown in years, months, and days.
  • Days Until Date CalculatorCount the days until a future date, with the gap also shown in years, months, and days. Free and browser-based.
  • Months Between DatesCount the whole calendar months between two dates, plus any leftover days.
  • Subtract Days from Date CalculatorSubtract a number of days from any date and get the resulting date and weekday, with month lengths and leap years handled.
  • Weeks Between DatesCount the number of weeks and leftover days between two dates, plus the total day count.
  • Years Between DatesFind the exact years, months, and days between two dates, with correct leap-year handling.

Time

  • 12 Hour to 24 Hour Time ConverterConvert a 12-hour AM or PM time to the 24-hour clock, with the 12 AM and 12 PM edge cases handled.
  • 24 Hour to 12 Hour Time ConverterConvert 24-hour, or military, time to a 12-hour AM or PM time, with 00:00 and 12:00 handled.
  • Hours Between Two TimesCalculate the hours and minutes between two clock times, including overnight spans, in your browser.
  • Hours to Decimal ConverterConvert hours and minutes to decimal hours and back, the way payroll and timesheets need it. Two decimal places, with total minutes.
  • Hours Worked CalculatorCalculate hours worked from clock-in and clock-out times minus a break. Handles overnight shifts and shows decimal and h:m totals.
  • Military Time ConverterConvert military (24-hour) time to standard 12-hour time and back, with correct handling of midnight and noon.
  • Minutes Between Two TimesCount the minutes between two clock times, with an option for spans that cross midnight.
  • Minutes to Hours ConverterConvert minutes into hours and minutes, plus a decimal-hours figure for timesheets and payroll.
  • Seconds to HH:MM:SS ConverterConvert a number of seconds into hours, minutes, and seconds, shown as HH:MM:SS. Handy for video, audio, and log durations.
  • Time Duration CalculatorCalculate the duration between two times in hours, minutes, and seconds, including overnight spans.

Calendar

  • Date to Roman Numerals ConverterConvert any date to Roman numerals for tattoos and invitations. Choose the day, month, and year order and the separator between them.
  • Date to Unix Timestamp ConverterConvert a date and time to a Unix timestamp in seconds and milliseconds. Enter any UTC date and time and get the epoch value instantly.
  • Day of the Week CalculatorFind the day of the week for any date, plus the day of the year, weekend status, and leap-year status.
  • Day of Year CalculatorFind the ordinal day number of any date, from 1 to 365 or 366, plus days remaining in the year.
  • Leap Year CalculatorCheck if a year is a leap year, see its number of days, and find the next leap year. Uses the full Gregorian rule, including the 100 and 400 year exceptions.
  • Week Number CalculatorFind the ISO 8601 week number for any date, with the ISO week-year and day of the week. Handles the week 53 and year-boundary cases correctly.

More tools

  • Days Left in Month CalculatorCount how many days are left in the month from any date, plus the total days in that month and how far through it you are. Leap years handled automatically.
  • Half Birthday CalculatorFind the date exactly six months after any birthday. Enter a birth date to get the month and day of the half birthday, with month-end dates handled correctly.
  • Julian Date ConverterConvert between a Gregorian calendar date and its Julian Day Number in both directions, using the standard astronomical day-count algorithm.
  • Quarter of the Year CalculatorSee which quarter a date falls in by calendar and fiscal year, with the start and end dates of that quarter. Set your own fiscal start month for fiscal quarters.