Hours calculator: hours between two times and weekly timesheet

How to calculate hours worked by hand

1. Write both times on the 24-hour clock: 5:15 pm is 17:15, and 12:00 am (midnight) is 00:00.
2. Subtract the minutes. If the end minutes are smaller, borrow an hour: add 60 to the end minutes and take 1 from the end hour.
3. Subtract the hours.
4. Take off the unpaid break.
5. Divide the leftover minutes by 60 to get decimal hours.

For a shift from 08:40 to 17:15 with a 45-minute unpaid lunch: 15 − 40 is negative, so borrow an hour and work out 75 − 40 = 35 minutes; then 16 − 8 = 8 hours. The shift spans 8 hours 35 minutes, and less the break it is 7 hours 50 minutes. As a decimal, 50 ÷ 60 = 0.8333, so the time worked is 7.83 hours.

The last step is where pay goes wrong. At $18.50 an hour, 7.8333 hours earns $144.92. Reading 7:50 as 7.50 hours pays $138.75, which is $6.17 short for one day.

Shifts that cross midnight

When the end time is earlier than the start, the shift finishes the next day, so add 24 hours to the end time before subtracting. A shift from 21:30 to 05:45 with a 30-minute break is (05:45 + 24:00) − 21:30 = 8 hours 15 minutes, less 30 minutes, which is 7 hours 45 minutes or 7.75 hours. The calculator does this itself when you enter the clock times as they appear.

In One shift mode, matching start and end times mean 24 hours. For a shift lasting more than one day, or for matching clock times that actually refer to the same instant, choose Dates & time zone and enter both dates explicitly.

Hours worked across daylight-saving changes

Choose Dates & time zone when a shift crosses a clock change. Enter the local date and time of each punch, the IANA zone where they were recorded, and the actual duration of the unpaid break. Use a name such as America/New_York or Europe/London; a fixed abbreviation such as EST does not describe a city's changing seasonal offset. Both endpoints use the same zone. For travel between different zones, first convert both endpoints to UTC with the time zone converter, then use UTC here.

The calculator resolves each local reading to an instant in UTC and subtracts those instants. It shows the clock difference, the adjustment caused by offset changes, and elapsed time before the break. A positive adjustment means more time elapsed than the clocks alone suggest; a negative adjustment means less time elapsed. This works for a half-hour change as well as a one-hour change.

For New York in 2026, compare these two overnight shifts. Both schedules read 23:00 to 07:30, with a 30-minute unpaid break:

These results match the US Department of Labor's daylight-saving shift example. The displayed UTC endpoints let you check which instants were used. Breaks are elapsed durations: if a break itself spans a clock change, determine its actual duration before subtracting it.

Repeated and skipped clock times

When clocks go back, a time may occur twice. In New York on 1 November 2026, the first 01:30 corresponds to 05:30 UTC and the second to 06:30 UTC. Selecting the first occurrence for the start and the second for the end gives one hour, even though the wall-clock readings match. Choose occurrences separately for each endpoint and check them against the original record. The calculator warns when either reading is ambiguous.

A forward change can remove a clock reading entirely. New York's 02:30 on 8 March 2026 never occurs, so the calculator reports an input error. It does not quietly substitute a different punch. This distinction between exact instants and ambiguous local readings is described in TC39's time-zone documentation.

Dates & time zone uses the rules available in your browser's time-zone database. Governments can change future rules, and older browsers can contain older data. It does not model leap seconds, payroll rounding, overtime eligibility or wage entitlements. The weekly timesheet remains a clock-based total; calculate affected shifts individually using dates before using their actual durations in a payroll record.

Minutes to decimal hours

Payroll systems and many timesheets want hours as a decimal. Each minute is 1/60 of an hour, so divide the minutes by 60. The table rounds to two decimal places, the usual precision on a timesheet.

Only multiples of 3 minutes come out exact at two decimals. The rest are rounded, and the rounding adds up: 7.83 hours at $18.50 is $144.86, six cents less than the exact 7 hours 50 minutes. The calculator sums shift durations before converting to decimal hours and rounds only the displayed figure, so add up minutes or seconds first and convert the total, not each day. To go the other way, multiply the decimal part by 60: 0.4 hours is 24 minutes.

Breaks and clock rounding

Enter only unpaid time as the break. If a shift has a 30-minute lunch and two paid 10-minute rest breaks, the break is 30 minutes. For a split lunch, add the pieces together. Some US states set minimum meal breaks: California Labor Code §512 requires a meal period of at least 30 minutes for a work period of more than 5 hours a day, which employer and employee can waive by mutual consent when the work day is no more than 6 hours.

Many time clocks round punches to the nearest 5 minutes, tenth of an hour (6 minutes) or quarter-hour. The US Department of Labor accepts that practice under 29 CFR 785.48(b) only if it averages out so that, over time, employees are paid for all the time they actually work. The calculator doesn't round: enter the recorded times, or round them first if your employer's policy does and you want to match your payslip.

Overtime under the FLSA

The US Fair Labor Standards Act requires employers to pay covered, non-exempt employees at least 1.5 times the regular rate for hours over 40 in a workweek (29 CFR 778.107; Fact Sheet #23). Two rules decide which hours count:

• The workweek is a fixed, regularly recurring period of 168 hours, seven consecutive 24-hour periods. It can start on any day and at any hour, so it need not run Monday to Sunday (29 CFR 778.105).
• Each workweek stands alone. Hours can't be averaged over two or more weeks, so 30 hours one week and 50 the next means 10 overtime hours, even though the fortnight averages 40 (29 CFR 778.104).

Five days of 08:00 to 17:30 with a 30-minute unpaid lunch make 9 hours a day and 45 hours a week. The timesheet splits that into 40 regular hours and 5 overtime hours. At $22 an hour, pay is 40 × $22 = $880 plus 5 × $33 = $165, a total of $1,045.

The FLSA counts only weekly hours, but some states also set daily overtime. Under California Labor Code §510, work over 8 hours in a workday is paid at 1.5 times the regular rate and work over 12 hours at double, alongside the weekly 40-hour rule. Four days of 07:00 to 17:30 with a 30-minute lunch total 40 hours, so the timesheet shows no overtime; under California's daily rule, 2 hours of each 10-hour day are overtime, and at $22 an hour the week pays 32 × $22 + 8 × $33 = $968 instead of $880. Section 510 doesn't apply to an alternative workweek schedule adopted under §511 or under a collective bargaining agreement (§514). The calculator applies only a weekly threshold, so work out daily overtime line by line from the timesheet table.

Reading the result

The calculator shows the same total two ways: decimal hours (7.75) for multiplying by a pay rate, and hours and minutes (7:45) for comparing with a clock. They are not interchangeable: 7:45 is 7.75 hours, not 7.45.

One shift and Weekly timesheet use clock readings; Dates & time zone measures actual elapsed time and reports any offset-change adjustment. To add several already-measured durations, including shifts checked for daylight saving, use the time calculator. To turn an hourly rate into annual pay, use the salary to hourly calculator.