Work hours calculator
This calculator adds up a full week of shifts in one place. Enter the start time, end time, and any unpaid break for each day, and it tallies the daily and weekly totals in hours, minutes, and decimal hours — with an optional gross-pay estimate. It is built for timesheets, shift work, and freelancers logging billable time.
How it works
For each day, the tool subtracts the start time from the end time to get the shift length, then deducts the unpaid break:
daily hours = (end − start) − break
If the end time is earlier than the start time, it adds 24 hours so overnight shifts count correctly. The daily figures are summed into a weekly total shown as hours-and-minutes and as decimal hours. If you expand the pay section and set an hourly rate, an overtime threshold (weekly hours), and a multiplier, hours above the threshold are paid at the higher rate for a gross-pay estimate.
| Input | Purpose |
|---|---|
| Start / End time | Defines each shift |
| Break (minutes) | Unpaid time subtracted |
| Hourly rate | Optional gross-pay basis |
| OT threshold / multiplier | Pays excess hours at a higher rate |
Example
A shift from 09:00 to 17:30 with a 30-minute unpaid break is 8.5 − 0.5 = 8 hours. Five such days give 40 hours for the week. At a £12 rate with a 37.5-hour overtime threshold and a 1.5 multiplier, the first 37.5 hours pay £450 and the extra 2.5 hours pay £45 (2.5 × 12 × 1.5), for £495 gross.
It is privacy-first: your hours, breaks and pay rate never leave your browser.
Why decimal hours matter for payroll
Payroll systems universally express time in decimal hours rather than hours and minutes, because decimal hours can be directly multiplied by an hourly rate. Hours and minutes cannot — you cannot multiply £12/hour by 7 hours 45 minutes to get a pay figure; you must first convert to 7.75 decimal hours. The conversion is minutes ÷ 60: 45 minutes becomes 0.75, so 7:45 → 7.75 decimal hours.
This tool shows both formats simultaneously so you can read the familiar hours-and-minutes for your own understanding and copy the decimal figure directly into payroll software or an invoice.
Common timesheet patterns and how they add up
Standard 37.5-hour week (UK common): Five days of 7.5-hour shifts (for example 09:00–17:00 with a 30-minute unpaid break each day). Total is exactly 37.5 hours, with no overtime unless extended.
40-hour week (US standard): Five days of 8-hour shifts. With a common 9:00–17:30 schedule and a 30-minute unpaid break, each day is exactly 8 hours and the week totals 40 hours.
Shift work with overnight crossings: A shift from 22:00 to 06:00 is correctly handled as 8 hours, not −16 hours. The tool detects when the end time is earlier than the start time and adds 24 hours to the elapsed calculation.
Split shifts: If you work two separate periods in a day (for example, 08:00–12:00 and 16:00–20:00), enter the combined break in the middle as unpaid time between the starts and ends — or enter each block separately in the next available day row and label them manually.
Overtime: how the threshold and multiplier work
In the overtime section you can set a weekly hours threshold (for example 40 hours) and a pay multiplier (for example 1.5 for time-and-a-half). Hours up to the threshold are paid at your normal hourly rate; any hours beyond are paid at rate × multiplier.
For example, a worker at £14/hour who works 44 hours against a 40-hour threshold at 1.5× earns: (40 × 14) + (4 × 14 × 1.5) = £560 + £84 = £644 gross. The calculator computes this without you needing to split the hours manually.
Note that overtime rules vary by country and employment contract. Some agreements use daily overtime thresholds (for example 8 hours per day) rather than weekly ones; this tool uses a weekly threshold only. The gross-pay figure is before tax, pension, and other deductions.