How the hours calculator works
For a single shift, the calculator takes your finish time away from your start time and then deducts any unpaid break. If the finish time is earlier than the start time, it assumes you worked past midnight and adds 24 hours, so a 10pm to 6am night shift counts as 8 hours.
hours worked = finish time − start time − unpaid break
pay = decimal hours × hourly rate
Switch to weekly timesheet to enter a start, finish and break for each day from Monday to Sunday. Leave days you didn't work blank and the calculator adds up the rest.
Converting hours and minutes to decimal hours
Payroll and timesheet systems usually need hours as a decimal, where 7 hours 30 minutes is 7.5 hours, not 7.30. To convert, divide the minutes by 60:
| Minutes | Decimal | Minutes | Decimal |
|---|---|---|---|
| 5 | 0.08 | 35 | 0.58 |
| 10 | 0.17 | 40 | 0.67 |
| 15 | 0.25 | 45 | 0.75 |
| 20 | 0.33 | 50 | 0.83 |
| 25 | 0.42 | 55 | 0.92 |
| 30 | 0.5 | 60 | 1 |
So 37 hours 45 minutes is 37.75 hours. Getting this wrong is a common reason for pay mistakes: 7.30 entered as a decimal would pay you for 7 hours 18 minutes instead of 7 hours 30.
Worked examples
A day shift
Start at 09:00, finish at 17:30 with a 30-minute unpaid lunch:
- 17:30 − 09:00 = 8 hours 30 minutes
- Take off 30 minutes = 8 hours (8.00 decimal hours)
- At £15 an hour: 8 × £15 = £120 before tax
A night shift
Start at 22:00 and finish at 06:15 the next morning with a 45-minute break. That's 8 hours 15 minutes on site, minus the break, so 7 hours 30 minutes, or 7.5 decimal hours. At £12 an hour that's £90.
A full week
Monday to Friday, 09:00 to 17:30 with a 30-minute break each day, comes to 40 hours. Add a Saturday from 10:00 to 14:00 and it's 44 hours, or £660 at £15 an hour.
Breaks and working hours rules in the UK
- Rest breaks: if you work more than 6 hours a day, you have the right to one uninterrupted 20-minute break. It doesn't have to be paid; that depends on your contract.
- Daily rest: workers are entitled to 11 hours' rest between working days.
- Weekly rest: you're entitled to an uninterrupted 24 hours without work each week, or 48 hours each fortnight.
- The 48-hour week: most workers can't be made to work more than 48 hours a week on average, normally measured over 17 weeks, unless they choose to opt out in writing.
- Minimum wage: your average pay for the hours you work must be at least the National Minimum Wage for your age. From April 2026 the National Living Wage for those aged 21 and over is £12.71 an hour, £10.85 for 18 to 20-year-olds and £8.00 for under-18s and apprentices.
Young workers (under 18) have different rules, including a 30-minute break if they work more than 4.5 hours.
Tips for keeping a timesheet
- Write times down as you go rather than at the end of the week.
- Note paid and unpaid breaks separately. Only take off the unpaid ones here.
- Keep copies of your timesheets and payslips, in case you need to check overtime or holiday pay later.
Paid more for extra hours? Use the overtime calculator. To turn a salary into an hourly figure try the hourly rate calculator, and see what you'll actually take home with the take-home pay calculator.
Frequently asked questions
How do I calculate hours worked?
Subtract your start time from your finish time and take off any unpaid break. For example, 08:30 to 17:00 with a 30-minute lunch is 8 hours 30 minutes minus 30 minutes, which is 8 hours.
How do I convert minutes to decimal hours?
Divide the minutes by 60. So 15 minutes is 0.25 hours, 30 minutes is 0.5 and 45 minutes is 0.75. 7 hours 45 minutes is 7.75 hours.
Are breaks paid in the UK?
Not necessarily. You have the right to a 20-minute rest break if you work more than 6 hours a day, but whether it's paid depends on your employment contract.
How many hours is 9am to 5pm?
9am to 5pm is 8 hours. With a 30-minute unpaid lunch break it's 7.5 hours, or 37.5 hours over a five-day week.
How do I work out hours for a night shift?
If you finish after midnight, add 24 hours to the finish time before subtracting the start time. 10pm to 6am is (6 + 24) − 22 = 8 hours. The calculator does this automatically.
Last reviewed October 2026 using 2026/27 figures. This calculator gives an estimate for guidance only.