✓ 100% FREE — No Signup Needed

Time Calculator

Add or subtract hours, minutes and seconds — total up shifts, project hours or workout times. Add as many rows as you need, instant results, 100% free.

How it works

Each row is a time duration in hours, minutes and seconds. Rows are combined with the operation you choose per row (+ or −). Seconds roll up into minutes and minutes into hours automatically — so 90 minutes correctly becomes 1h 30m.

FAQs

How do I add two time durations?

Enter each duration as hours, minutes and seconds, choose the + operation, and press Calculate. For example, 2h 30m + 1h 45m = 4h 15m.

Can I subtract time too?

Yes — select the − operation to subtract one duration from another, useful for elapsed-time and shift calculations.

Can I add more than two times?

Yes. Use the add-row button to total as many durations as you need — handy for timesheets and project hours.

Is this time calculator free?

Yes, 100% free with no signup. All calculations run in your browser.

How do I convert decimal hours to hours and minutes?

Multiply the decimal part by 60: 7.75 hours = 7 hours + (0.75 × 60) = 7h 45m. Going the other way, divide minutes by 60: 7h 45m = 7 + 45÷60 = 7.75h. Payroll systems almost always want the decimal form.

How do I calculate the time between two clock times?

Subtract start from end. If the end time is earlier than the start (an overnight shift from 22:00 to 06:00), add 24 hours to the end first: (6 + 24) − 22 = 8 hours. Then subtract any unpaid break.

Why do I keep making mistakes adding minutes past 60?

Because time is base-60, not base-100: 45 + 30 minutes is 75 minutes, which carries to 1h 15m. The foolproof method is converting every duration to total minutes first, adding, then converting back once at the end.

How time addition and subtraction work

Time math trips people up because hours, minutes, and seconds use base 60, not base 100 — 1.5 hours is 1 hour 30 minutes, not 1 hour 50 minutes. The calculator sidesteps the confusion with one method: convert everything to the smallest unit, do ordinary arithmetic, then convert back.

The method, with worked examples

Addition: 2h 45m + 1h 30m → 165 + 90 = 255 minutes → 255 ÷ 60 = 4 remainder 15 → 4h 15m. Subtraction with borrowing: 5h 10m − 1h 45m → 310 − 105 = 205 minutes → 3h 25m (the calculator borrows 60 minutes automatically, the way you borrow 10 in decimal subtraction). Clock-time difference: end − start; if the end time is earlier (overnight shift 22:00→06:00), add 24 hours first: (6 + 24) − 22 = 8 hours.

Practical tips

For timesheets and payroll, convert to decimal hours: multiply the minutes by 60 — 7h 45m = 7 + 45÷60 = 7.75h. Reverse it by multiplying the decimal part by 60: 0.75 × 60 = 45 minutes. And when adding a long list of durations, convert each to minutes first and add once — chaining hour:minute additions by hand is where the carry errors creep in.

Timesheets, rounding, and payroll gotchas

Real timesheets add one more rule: rounding policy. Many employers round to the nearest 15 minutes (7:53→8:00) or 6 minutes (tenths of an hour); US labour guidance permits rounding only if it averages out neutrally over time — consistently rounding against the employee is wage theft by another name. When totalling a week, add in minutes and convert once at the end rather than rounding each day, or rounding dust accumulates. For billing clients, most freelancers round up to the nearest 6–15 minute increment and state the policy in the contract — transparency upfront prevents every dispute later. Keep the raw start/end times logged; you can always re-total, but you can never reconstruct times you did not write down.

Adding up a whole timesheet

For a full week, resist adding day-by-day in hours:minutes — convert each day to minutes, sum once, then convert back. Example: 8h15 + 7h45 + 8h30 + 6h50 + 8h05 becomes 495 + 465 + 510 + 410 + 485 = 2,365 minutes = 39h 25m (39.42 decimal hours). One conversion at the end means one chance of error, not five.

Related Tools

More free tools you may like

Work Hours CalculatorShifts and pay Date DifferenceDays between dates StopwatchOnline timer Time Zone ConverterWorld clock Countdown TimerCount to any date