Time Calculators

Choosing the right time calculator

All three tools measure the same thing — the gap between two clock readings — but they present it for different purposes.

• Time duration — a single period, in hours, minutes and decimal hours. Use it for anything that is not about pay.
• Hours worked — one shift, with an unpaid break deducted, payroll rounding, and optional pay.
• Timesheet calculator — a whole week of shifts, with a weekly overtime threshold and a day-by-day table.

Decimal hours, and why they matter

Payroll systems want hours as a decimal, not as hours and minutes. Seven hours and thirty minutes is 7.5, not 7.30. Writing 7.30 understates the shift by twelve minutes, and repeated across a month and a team it is a real amount of money. Every calculator here shows both formats side by side so the two cannot be confused.

The conversions worth memorising:

• 15 minutes = 0.25
• 20 minutes = 0.33
• 30 minutes = 0.5
• 45 minutes = 0.75
• 50 minutes = 0.83

Shifts that cross midnight

A finish time earlier than the start time is treated as running into the next day, so 22:00 to 06:00 is eight hours rather than a negative figure. Times are held internally as minutes past midnight rather than as clock arithmetic, which means a daylight-saving change can never silently add or remove an hour from someone's pay.

Paid and unpaid breaks

Only unpaid breaks should be deducted. A paid rest break is part of your working time, and entering it as a break understates your hours. If you are unsure which yours are, check your contract — the distinction is usually explicit.

Rounding

Many employers round clock-in and clock-out times to the nearest 5, 6 or 15 minutes. Rounding to the nearest increment evens out over time. Rounding that always goes one way does not, and the hours worked calculator shows you the difference between the exact and rounded figures so you can see which you are dealing with.