Time & Date

Work Hours Calculator

Enter clock-in and clock-out times and the break. Add as many periods as you need — the total comes out in both h:mm and the decimal hours payroll asks for.

This calculator needs JavaScript to run. The formula, the worked examples and the explanations below all work without it.

Period 1

Add an hourly rate (optional)
Leave empty to skip the pay estimate
An overnight shift is detected automatically when the end time is earlier than the start.

How the calculation works

For each period the calculator takes the end time minus the start time, adds 24 hours if the shift crossed midnight, and subtracts the break. Then it adds every period together.

Formulanet = (end − start, +24 h if it crosses midnight) − break

Everything is done in whole minutes and converted at the end, so a week of entries adds up exactly. The decimal-hours figure is what payroll systems want: net minutes ÷ 60.

Overnight shifts

If the end time is earlier than the start time, the shift is assumed to run into the next day. 22:00 to 06:00 is eight hours, not minus sixteen. The result labels those rows so you can see the assumption was made.

The one case that stays ambiguous is a start and end that are identical. Rather than guess between "zero hours" and "a full 24-hour shift", the calculator asks you to make it explicit — use 00:00 to 23:59 if you really did work around the clock.

Daylight-saving changeovers are not applied. Twice a year an overnight shift is really 7 or 9 hours rather than 8. If that matters for your payroll, adjust that one shift by hand — assuming a time zone you might not be in would cause more errors than it fixed.

Breaks: paid, unpaid, and what to enter

Enter the break minutes you are not paid for. In most US workplaces a 30-minute unpaid meal break is standard, while short rest breaks of 5–20 minutes are usually paid and should not be entered here.

If you take several breaks in one period, add them up and enter the total. If a break splits your day into two genuinely separate blocks — a long midday gap, a split shift — enter them as two periods instead. The totals are the same, but the record is clearer.

What you workedHow to enter it
9 to 5 with an unpaid half-hour lunchOne period, 09:00 → 17:00, break 30
Split shift: 09:00–13:00 and 17:00–21:00Two periods, no break on either
Night shift 22:00 → 06:00 with a 45-minute breakOne period, break 45 — the overnight roll is automatic
A whole weekOne period per day, up to twelve

Worked examples

09:00 to 17:30, 30-minute unpaid lunch

8 h 30 m gross, minus 30 minutes = 8h 00m net, which is 8.00 decimal hours.

Night shift 22:00 to 06:00, no break

The end is earlier than the start, so a day is added: 8h 00m.

Three periods in one day: 09:00–13:00, 14:00–18:00, 20:00–22:30 with a 15-minute break

4 h + 4 h + 2 h 15 m = 10h 15m, or 10.25 decimal hours.

Turning hours into pay

Gross pay is decimal hours × hourly rate. 8.00 hours at $18.50 is $148.00. The optional rate box does this for you, and it uses net hours — breaks are not paid.

What it deliberately does not do is overtime, shift differentials, tax or deductions. Overtime rules vary by country, state and contract; a number that looked authoritative but used the wrong rule would be worse than no number at all. Treat the figure as gross pay for regular hours.

Common uses

  • Checking a paycheque against the hours you actually worked.
  • Freelance invoicing where clients want decimal hours.
  • Small-team timesheets without payroll software.
  • Shift work with nights and split shifts.
  • Contract compliance — checking break entitlements and weekly totals.

Frequently asked questions

How do I calculate hours worked with a lunch break?
Subtract the start time from the end time, then subtract the unpaid break. 09:00 to 17:30 is 8 hours 30 minutes; take off a 30-minute lunch and you have 8 hours exactly. Enter only breaks you are not paid for.
How does it handle a night shift that crosses midnight?
Automatically. When the end time is earlier than the start time the calculator adds 24 hours, so 22:00 to 06:00 comes out as 8 hours. The row is labelled so you can see the assumption.
What are decimal hours and why does payroll want them?
Decimal hours express minutes as a fraction of an hour, so 8 hours 15 minutes is 8.25. Payroll systems need them because you cannot multiply 8:15 by an hourly rate directly. The classic mistake is writing 8.15 for 8 hours 15 minutes, which is nine minutes short.
Can I add up a whole week?
Yes — add one period per day, up to twelve. The total, the break time and the decimal hours all accumulate across every period.
Does the pay estimate include overtime or tax?
No. It is net hours multiplied by your rate, nothing more. Overtime multipliers, shift premiums, tax and deductions all depend on rules that vary by jurisdiction and contract, so applying them here would produce confident-looking wrong numbers.
Why can't the start and end time be the same?
Because it is genuinely ambiguous — it could mean no time worked or a full 24 hours. Rather than pick one silently, the calculator asks you to say which. For a full day, enter 00:00 to 23:59.