Date & Time Tools

Timestamps, timezones, durations and business-day calculations.

Add or Subtract Time Shifts a whole list of dates forward or back, and says where a month end had to be clamped.
Age Calculator Turns a list of dates of birth into exact ages, as at today or any date you name.
Business Day Calculator Counts working days between dates, or adds business days to one, using your holidays and your weekend.
Cron Explainer Translates cron expressions into English and shows the next runs in the timezone you choose.
Date Difference Measures the gap between pairs of dates in calendar terms and in plain totals, both at once.
Date Format Converter Reformats a list of dates into one consistent form, and flags the ones that were ambiguous.
Duration Formatter Reads a duration in any of the four common notations and shows it in all of them.
ISO Week Calculator Gives the ISO 8601 week number, weekday, day of year and quarter for every date you paste.
Timestamp Converter Converts epoch and ISO timestamps into readable dates, in bulk, with the timezone spelled out.
Timezone Converter Converts a list of times between two IANA zones, applying daylight saving as it stood on each date.
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