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Time & Date tool map

Time & duration

Clock time, elapsed time, and time zones.

Choose the tool whose inputs and output match your task. Check each calculator’s assumptions and limitations before using its result.

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Clock-time questions need different tools than calendar dates. The time duration calculator measures the interval between two clock times, adds time to a base time, or subtracts an interval — pick Time Difference when you know a start and end, or Add and Subtract Time for a resulting clock time. When one shift is the unit of work, the shift calculator derives start or end times from a known duration plus unpaid break, keeping working time separate from the clock span. If the two clocks are not in the same zone, convert first with the time zone calculator, using daylight-saving rules for that date. Weekly payroll and scheduling round out the Time & Date collection.

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Frequently asked questions

How do I calculate the end time for an 8 hour shift?
Select start time as the known value, enter the start in 24-hour format, set the shift duration to 8 hours, and add any unpaid break minutes. The calculator adds working minutes and break minutes together, then rolls the result around the 24-hour clock if the shift ends after midnight.
Can the shift calculator work backward from an end time?
Yes. Choose end time as the known time, enter the clock time you must leave, and keep the same duration and break settings. The calculator subtracts the total clock span from the end time, so it is useful for planning when to arrive before a required handoff or closing time.
Does break duration count inside the shift time?
The calculator treats the entered shift duration as effective working time, excluding breaks. Break minutes are then added to create the clock span between start and end. An 8 hour shift with a 30 minute unpaid meal period therefore covers 8 hours 30 minutes on the clock.

More in Time & Date

Dates & calendars

Related comparisons

All Time & Date comparisons →
Age vs Time DurationChoose between a calendar-age calculator that breaks a birth date to any date into years, months, and days with a next-birthday countdown, and a clock calculator that measures or shifts intervals between times of day.Business Days Between Dates vs Time DurationCompare counting Monday-to-Friday working days between calendar dates, with holidays excluded, and measuring elapsed clock time between times of day, with totals in hours, minutes, and seconds.Military Time vs Time Duration CalculatorCompare the military time and time duration calculators: four-digit 24-hour clock notation in both directions versus elapsed time, add, and subtract modes with totals in hours, minutes, and seconds.Shift Calculator vs Time Card CalculatorChoose between a single-shift start and end time planner with unpaid breaks, and a weekly timesheet that totals regular and overtime hours across selected workdays.Shift vs Time Duration CalculatorCompare the two clock-math calculators: 8-hour shift start/end planning with an unpaid break versus generic elapsed-time measurement with add and subtract modes.Time Converter vs Time Duration CalculatorCompare the time converter, which converts a duration among seconds, minutes, hours, days, weeks, and average months and years, with the time duration calculator, which measures the span between two clock times and adds or subtracts time.Time Duration vs Date DurationCompare the time duration calculator's clock-interval math with the date duration calculator's calendar span: hours, minutes, and seconds versus years, months, days, and exact day counts.Time Duration vs Time Card CalculatorCompare measuring a single clock interval in hours, minutes, and seconds against totaling weekly work hours with lunch deductions and overtime.Time Zone Calculator vs Time Zones ConverterCompare the date-aware IANA time zone calculator with the fixed-UTC-offset converter: named places with daylight saving rules versus offset arithmetic without a city database.Time Zone vs Time Duration CalculatorCompare the time zone calculator with the time duration calculator: converting one instant between zones versus measuring elapsed time between clock readings.

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