Time Calculator
Add, subtract, and convert time durations and intervals effortlessly.
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Quick Tip
Enter the hours.
About This Tool
Why use Time Calculator?
Convert a duration written in hours and minutes into total minutes, total seconds and decimal hours. The decimal figure is the one timesheets, invoices and payroll systems use: 2 hours 45 minutes is 2.75 hours, not 2.45.
Minutes convert by dividing by 60, so 15 minutes is 0.25, 30 is 0.5 and 45 is 0.75. Totals are useful elsewhere: 2 hours 45 minutes is 165 minutes or 9,900 seconds, which is the format video editors and schedulers tend to work in.
Key Benefits
Decimal hours without mistakes
The conversion most people get wrong by hand, done correctly every time.
Minutes and seconds totals
Useful for media timing, cooking and anything measured in a single unit.
Instant and reversible
Change either field and every total updates, so you can work in whichever direction suits.
How to use Time Calculator
- 1
Enter the hours.
- 2
Enter the minutes.
- 3
Read the total minutes, total seconds and decimal hours.
- 4
Use decimal hours for billing and payroll, and totals for scheduling.
Best use cases
Convert worked hours for a timesheet or invoice.
Turn a duration into minutes for scheduling.
Work out total seconds for video or audio timing.
Check a billing total against a rate per hour.
Time Calculator FAQs
How do I convert hours and minutes to decimal hours?
Divide the minutes by 60 and add them to the hours. 3 hours 20 minutes is 3 + 0.33 = 3.33 hours.
Why is 1.5 hours 90 minutes and not 150?
Decimal hours are fractions of 60 minutes, not of 100. The 0.5 means half an hour, which is 30 minutes.
How many seconds are in an hour?
3,600 — 60 minutes of 60 seconds each.
How do I add several durations together?
Convert each to total minutes, add them, then divide by 60 for hours and take the remainder as minutes.
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