Date Difference Calculator
Pick two dates (optionally with times) to get the difference in years-months-days, total days, weeks, months, hours, minutes and seconds, plus business days that respect a custom workweek and a pasted holiday list. Add or subtract days, business days, weeks, months, years, hours or minutes from a date; calculate an age with the next-birthday countdown, days lived and milestone dates; or run a live countdown to any target. Each endpoint shows its weekday, ISO week, quarter and day of year, and everything can be copied or downloaded.
Enter two valid dates.
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How to use Date Difference Calculator
- 1Choose Difference, Add / subtract, Age or Countdown.
- 2Enter the dates (turn on time of day if you need it); set your workweek and paste holidays in Options.
- 3Read the totals, business days and per-endpoint calendar facts; copy or download them.
About Date Difference Calculator
Pick two dates (optionally with times) to get the difference in years-months-days, total days, weeks, months, hours, minutes and seconds, plus business days that respect a custom workweek and a pasted holiday list. Add or subtract days, business days, weeks, months, years, hours or minutes from a date; calculate an age with the next-birthday countdown, days lived and milestone dates; or run a live countdown to any target. Each endpoint shows its weekday, ISO week, quarter and day of year, and everything can be copied or downloaded.
Date Difference Calculator is part of FizzKit — a collection of focused developer and ad-tech tools. Because everything runs locally, it works offline once loaded and never exposes your data to a remote server.