Timesheet Calculator

How to use this calculator

1. Use 24-hour times09:00 and 17:30, not 9am and 5.30pm. A finish earlier than the start is treated as a shift crossing midnight, which is how night shifts are handled.
2. Enter breaks in minutesOnly unpaid breaks. If your break is paid, leave it at zero — deducting a paid break understates your hours.
3. Leave unworked days blankBoth fields empty means the day is skipped entirely rather than counted as zero.
4. Set the overtime threshold to your contractForty hours is common but not universal. Some contracts use 37.5, and some calculate overtime daily rather than weekly.

Decimal hours are not clock time

This is the single most common error in manual timesheets, and it is worth stating baldly because it costs people money.

Payroll works in decimal hours. Timesheets are filled in using clock time. The two look similar and are not the same, because an hour has sixty minutes rather than a hundred.

Seven hours and thirty minutes is 7.5 decimal hours. Written as 7.30 it looks like a smaller number, and someone adding a column of such figures gets a total that is wrong in a way that is hard to spot.

The conversion is minutes divided by sixty. Fifteen minutes is 0.25, twenty minutes is 0.333, forty-five minutes is 0.75. The awkward ones are the thirds — twenty and forty minutes do not convert to neat decimals, which is why some employers round to the nearest quarter hour.

Rounding practice varies and matters over a year. Rounding each shift to the nearest quarter hour is common and broadly neutral if applied consistently in both directions. Rounding down only is not neutral, and a policy that always rounds against the worker is a deduction from wages by another name.

Shifts crossing midnight are the second trap. A shift from 22:00 to 06:00 shows a finish time numerically lower than the start, and subtracting directly gives minus sixteen hours. The correct treatment is to add twenty-four, giving eight hours. This calculator detects that case and flags it, because a manual timesheet showing a negative figure usually gets silently corrected to something wrong.

Breaks then come off the total. A twenty-two-thirty to six-thirty shift with a thirty-minute unpaid break is eight hours minus thirty minutes, so 7.5 decimal hours.

Worked example: five days plus a Saturday morning

Monday to Friday, 09:00 to 17:30 with a thirty-minute unpaid break each day.

Each day is 8 hours 30 minutes gross, less 30 minutes, giving 8 hours exactly. Five days is 40 hours.

Saturday, 09:00 to 13:00 with no break, is 4 hours.

Total: 44 hours across six days.

Against a 40-hour basic threshold, that is 40 basic hours and 4 overtime hours.

At £15 an hour, basic pay is 40 × £15 = £600. Overtime at time and a half is 4 × £15 × 1.5 = £90.

Gross pay: £690.

The average rate across all 44 hours is £15.68 — higher than the basic rate, because of the overtime premium. That average is a useful figure when comparing jobs where one pays more basic and the other offers more overtime.

Now note what the break deduction cost. Five thirty-minute breaks is 2.5 hours a week, or roughly 115 hours a year — nearly three working weeks. At £15 that is £1,725 of unpaid time. Whether breaks are paid is a genuine part of a job's value, and it is routinely overlooked when comparing offers.

And 44 hours is under the 48-hour average limit, so no working time question arises. But it is worth remembering that the limit is an average over seventeen weeks rather than a weekly cap — a single 55-hour week is not a breach if the average holds.

Minutes to decimal hours

Only the quarter hours convert cleanly — 15, 30 and 45 minutes give 0.25, 0.5 and 0.75. Everything else recurs, which is why rounding policies exist and why a timesheet totalled in clock time and then read as decimal produces errors that are small per shift and substantial over a year.

Breaks, working time and getting paid correctly

Workers over eighteen are entitled to an uninterrupted rest break of at least twenty minutes when working more than six hours in a day. The break must be during the shift rather than at the start or end, and the worker is entitled to spend it away from their workstation.

There is no statutory requirement for that break to be paid. Whether it is comes down to the contract, and the difference is worth real money over a year.

Daily rest of eleven consecutive hours between working days is also a statutory entitlement, as is weekly rest of either twenty-four uninterrupted hours each week or forty-eight hours each fortnight.

The forty-eight-hour weekly limit is an average over a seventeen-week reference period, not a hard weekly cap, and workers can opt out of it in writing. The opt-out must be voluntary, can be withdrawn with notice, and cannot be made a condition of employment. Some sectors have different rules, and young workers have stricter protections.

Overtime itself is contractual. There is no statutory right to be paid extra for hours beyond your normal week — the only statutory constraint is that average pay across all hours worked must not fall below the National Minimum or Living Wage for your age band. A salaried employee working substantial unpaid overtime can breach that floor, and that is worth checking rather than assuming.

On record-keeping, employers must keep adequate records of hours worked to demonstrate compliance with the working time limits. Workers are well advised to keep their own record too, since a dispute about hours is very hard to win without contemporaneous notes.

For anyone paid by the hour, checking the payslip against your own timesheet each period is worth the few minutes it takes. Errors in either direction are common, and they compound quietly.

Assumptions and limitations

• Assumes one continuous shift per day — split shifts need entering as separate weeks or summing manually
• Treats a finish earlier than the start as crossing midnight
• Assumes the break entered is unpaid; leave it at zero if your break is paid
• Overtime is split at a weekly threshold, not a daily one
• Does not apply National Minimum Wage checks
• Does not model night-shift premiums, weekend rates or bank holiday enhancements
• Gross pay before tax and National Insurance

Questions people ask about this in United Kingdom