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Time & hours

Time and hours calculators

Everything you need to count working time: hours and minutes, shifts that cross midnight, unpaid breaks, weekly overtime and 24-hour clock times. Pick the one that fits what you're doing.

Updated October 8, 2026

Time calculatorAdd or subtract hours and minutes, or find the time between two clock times.Time card calculatorClock in and out for the week, with breaks, overtime and pay.Time duration calculatorTotal several start and end times, including overnight shifts.Overtime calculatorTime-and-a-half and double-time pay from your hourly rate.Military time converterSwitch between 12-hour and 24-hour time, with a full chart.
Calcowa owl clocking in at a punch clock at the start of a shift

Which calculator do I need?

If you're adding a few durations together, like 2:45 plus 1:30, the time calculator's the quickest. If you've got clock-in and clock-out times for a whole week, use the time card calculator, which also splits off overtime past 40 hours. For a single day with several parts, like a split shift, the time duration calculator's built for it. And when you already know your hours and just want the pay, go straight to the overtime calculator.

Why time math trips people up

An hour's 60 minutes, so time doesn't add like decimals. 7:45 isn't 7.45 hours, it's 7.75. That's the mistake that shows up on timesheets most often, and it's why every calculator here shows the answer both ways. Shifts that cross midnight are the other one: you can't subtract 22:00 from 06:00 without adding a day first, and the calculators do that for you.

None of them ask you to sign up, and there's no lead form between you and the answer. They don't store what you type, either; it's all worked out in your browser, so you're free to try different numbers until they match your timesheet.

If you've worked a night shift, don't worry about the date flip; just type the times as they were. And if you're in Brazil, there's a Portuguese section that's built around the CLT rules, including the night hour that's counted as 52 minutes and 30 seconds. You'll find it under the PT button at the top.