Duration Calculator
Calculate precise differences in dates and times. Subtract break times and customize event inclusivity.
Timeline
Provide input dates to calculate duration.
Related Time & Date Tools
How time duration is computed
Time spans are calculated by taking differences in UTC epoch millisecond boundaries. The calendar breakdown (years, months, days, hours, minutes, seconds) steps through calendar months to correctly adjust for leap years and differing month lengths.
By adjusting break minutes, the tool decrements total milliseconds to enable precise workplace time card evaluations. Inclusive counting parameters increase the final span by 24 hours to model full workdays.
Private & free — this tool runs entirely in your browser.
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