Duration Calculator
Calculate the difference between two dates, or add/subtract time.
Difference between two dates
Enter valid start and end dates.
Add / subtract duration
Enter a valid start date and amount.
About the Duration Calculator
Find the exact difference between two datetimes broken into years, months, days, hours, minutes and seconds, plus totals. Also add or subtract a custom duration from a date.
Examples
Days between
2026-01-01 to 2026-08-06Output
7 months, 5 daysRelated tools
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Frequently asked questions
Version 1.0.0 · Updated 2026-08-06 · Runs entirely in your browser