Work and taxes
Time Calculator: Add and Subtract Hours
Add hours, count the time between two times or find what time it will be, without tripping over the 60 minutes
With this time calculator you can add hours and minutes, or subtract them, without doing the math in your head: type one time per line and we give you the total in hours and minutes, in decimal hours and in minutes. It also finds the time between two times, across midnight too, and what time it will be after a number of hours.
The key idea
Hours do not add up like decimals: they work in base 60
1:45 plus 0:30 is not 1:75, it is 2:15, because every 60 minutes make an hour. And 1.5 hours is 1 h 30 min, not 1 h 50 min. Mixing up decimal hours and clock time is a common mistake when adding hours on a timesheet or an invoice.
How it is calculated
The calculator does three things. Everything is turned into minutes first, because hours work in base 60:
- Add or subtract hours and minutes: each time on its line becomes minutes, we add them up (or subtract the ones with a minus sign) and write the total back in hours and minutes.
- Time between two times: end time minus start time. If the end is earlier, the period crosses midnight, so we add 24 hours: from 10:30 PM to 6:15 AM is 7 h 45 min.
- What time it will be: the start time plus or minus the amount of time, wrapping around midnight and counting the days: 9:15 AM plus 8 h 30 min is 5:45 PM.
Minutes = hours × 60 + minutes · Hours = minutes / 60 (and the remainder, minutes)
Decimal hours are what many spreadsheets, payroll systems and invoices ask for: 2 h 15 min is 2.25 hours, because 15 minutes is a quarter of an hour. Clock times are shown in 12-hour format with AM and PM, and in 24-hour (military) time.
Worked example
2:30 + 1:45 + 0:50 − 0:15:
150 + 105 + 50 − 15 = 290 min = 4 h 50 min = 4.83 hours
Typical cases
Minutes to decimal hours chart
Timesheets and payroll often need hours as a decimal: divide the minutes by 60. Here are the most common ones.
| Time (h:mm) | Decimal hours | Total minutes |
|---|---|---|
| 0:05 | 0.08 | 5 min |
| 0:10 | 0.17 | 10 min |
| 0:15 | 0.25 | 15 min |
| 0:20 | 0.33 | 20 min |
| 0:25 | 0.42 | 25 min |
| 0:30 | 0.50 | 30 min |
| 0:35 | 0.58 | 35 min |
| 0:40 | 0.67 | 40 min |
| 0:45 | 0.75 | 45 min |
| 0:50 | 0.83 | 50 min |
| 0:55 | 0.92 | 55 min |
| 1:00 | 1.00 | 60 min |
| 1:15 | 1.25 | 75 min |
| 1:30 | 1.50 | 90 min |
| 1:45 | 1.75 | 105 min |
| 7:30 | 7.50 | 450 min |
| 8:00 | 8.00 | 480 min |
Save or share this table as an image Typical cases
Military time chart: 24-hour to 12-hour time
Military time counts the hours of the day from 00 to 23, with no AM or PM. From 13:00 on, subtract 12 to get the afternoon and evening hour.
| Military time | Standard time | Military time | Standard time |
|---|---|---|---|
| 00:00 | 12:00 AM | 12:00 | 12:00 PM |
| 01:00 | 1:00 AM | 13:00 | 1:00 PM |
| 02:00 | 2:00 AM | 14:00 | 2:00 PM |
| 03:00 | 3:00 AM | 15:00 | 3:00 PM |
| 04:00 | 4:00 AM | 16:00 | 4:00 PM |
| 05:00 | 5:00 AM | 17:00 | 5:00 PM |
| 06:00 | 6:00 AM | 18:00 | 6:00 PM |
| 07:00 | 7:00 AM | 19:00 | 7:00 PM |
| 08:00 | 8:00 AM | 20:00 | 8:00 PM |
| 09:00 | 9:00 AM | 21:00 | 9:00 PM |
| 10:00 | 10:00 AM | 22:00 | 10:00 PM |
| 11:00 | 11:00 AM | 23:00 | 11:00 PM |
Save or share this table as an image Common questions
Frequently asked questions
How do you add hours and minutes?
Turn them into minutes, add them and convert back to hours: 1:45 + 0:30 is 105 + 30 = 135 minutes, which is 2 h 15 min.
How do I convert hours and minutes to decimal hours?
Divide the minutes by 60 and add them to the hours: 2 h 15 min is 2 + 15 / 60 = 2.25 hours.
How do I calculate the time between two times?
Subtract the start time from the end time. If the end is earlier, the period crosses midnight, so add 24 hours: from 10:30 PM to 6:15 AM is 7 h 45 min. Choose “Time between two times” and the calculator does it.
Can I subtract time?
Yes: put a minus sign in front of the time you want to subtract, for example −0:15 to take off a break.
Can I use it to total my work week?
Yes, though if you have the clock-in and clock-out time for each day, the hours worked calculator is easier, because it subtracts your breaks for you.
How do I find what time it will be in a number of hours?
Add the hours to the current time and subtract 12 (or 24) each time you pass noon or midnight: 9:15 AM plus 8 h 30 min is 5:45 PM. Choose “What time it will be” and it also tells you if it falls on another day.
Hours, overtime and rates
Work and taxes
You may also need
Your next calculation
Missing a calculator?
Tell us what you need to calculate. The most requested ones are the first we build, with their formula, a worked example and the source.