Time to decimal calculator
2 hours 20 minutes 42 seconds is 2.345 hours in the time to decimal calculator: 2 + 20 ÷ 60 + 42 ÷ 3,600.
Decimal hours
- Result
- 2 h 20 min 42 s
- As hours:minutes:seconds Hours are not rolled into days here, which is how a timesheet or a race total is written.
- 2:20:42
- In decimal hours Total seconds divided by 3,600. This is the form an hourly rate multiplies.
- 2.345 h
- Decimal hours, by the units Minutes are sixtieths of an hour and seconds are 3,600ths, so each is divided down and added to the whole hours.
- 2 + 20 ÷ 60 + 42 ÷ 3,600 = 2.345
- In minutes
- 140.7 min
- In seconds
- 8,442 s
- In days
- 0.097708333 days
- Working Each time is converted to seconds (days × 86,400 + hours × 3,600 + minutes × 60 + seconds), the seconds are added or subtracted, and the total is split back into units.
- 2 h 20 min 42 s = 8,442 s; 0 s = 0 s; 8,442 + 0 = 8,442 s = 2 h 20 min 42 s
How the Time Calculator works
Decimal hours = hours + minutes ÷ 60 + seconds ÷ 3,600. A minute is a sixtieth of an hour and a second is a 3,600th, so each is divided down to hours and added to the whole hours.
For 2:20:42: 20 ÷ 60 = 0.3333 and 42 ÷ 3,600 = 0.0117, so 2 + 0.3333 + 0.0117 = 2.345 hours. For 7:50: 50 ÷ 60 = 0.8333, so 7.8333 hours, with the 3 repeating.
Payroll multiplies a rate by decimal hours. 7 hours 50 minutes at $18 an hour is 7.8333 × 18 = $141.00. Reading it as 7.50 hours would pay $135.00.
Only some minute counts give a decimal that ends. Every multiple of 3 minutes is an exact multiple of 0.05 hours (3 minutes = 0.05, 6 = 0.1, 15 = 0.25), and the rest repeat, which is why payroll rounds to two places.
For decimal minutes instead of hours, divide the seconds by 60: 4 minutes 30 seconds is 4.5 minutes.
Time Calculator FAQ
What is 45 minutes as a decimal?
0.75 hours, from 45 ÷ 60.
What is 8 hours 20 minutes in decimal?
8.3333 hours, since 20 ÷ 60 = 0.3333.
How do I add up times and get decimal hours?
Add the times first, carrying every 60 minutes into an hour, then convert the total: 3:40 + 4:35 = 8:15, which is 8.25 hours.
How do I turn decimal hours back into hours and minutes?
Multiply the decimal part by 60 for the minutes, and the decimal part of that by 60 for the seconds. 2.345 hours is 2 hours and 0.345 × 60 = 20.7 minutes, which is 20 minutes 42 seconds.