Hours Calculator
Add and subtract hours and minutes, line by line
Type each duration as 1:30 or as 1.5 and choose whether it adds to the total or comes off it. The running total is shown after every line, so you can see where a figure went wrong without starting again.
Use the plus and minus button on the left of a line to switch it between adding and subtracting.
How this hours calculator works
Time is not decimal, which is why adding it on a normal calculator goes wrong. 7:45 plus 6:30 is not 13.75 or 14.15 - it is 14:15, because the minutes carry at sixty, not at a hundred. This page converts every line to whole minutes first, adds or subtracts them, and converts back only for display.
Minutes for a line = hours x 60 + minutes
Total = the added lines' minutes - the subtracted lines' minutes
Displayed time = total / 60 hours and total mod 60 minutes
•
Each line can be typed as hh:mm (2:20) or as decimal hours (2.33) - both are accepted, and you can mix them in one list.
•
The running total on the right of each line is the total up to and including that line.
•
Totals never wrap at 24 hours, so a working week shows as 41:15 rather than 17:15.
•
Subtracting more than you have added gives a negative total, which is exactly what a flexitime balance needs.
Worked example
Two work blocks and a long lunch that came out of the middle of the second one:
+ 7:45 = 465 minutes (running total 7:45)
+ 6:30 = 390 minutes (running total 14:15)
- 1:15 = 75 minutes (running total 13:00)
Total 780 minutes = 13:00 = 13.00 decimal hours
The same list on a pocket calculator, typed as 7.45 + 6.30 - 1.15, gives 12.60 - nearly half an hour adrift, and adrift in the direction that costs you money.
When a running total earns its keep
A single grand total tells you the answer is wrong but not where. The running total column tells you which line broke it: scan down until the number stops matching your expectation and the mistake is on that line. It is the same reason a bank statement shows a balance after every transaction rather than only at the bottom.
Adding hours to a time of day
To add hours to a clock time, add the whole hours first and then the minutes: 8:30 AM plus 9 hours is 5:30 PM. Once the running answer goes past 12:59 the AM flips to PM, and once it goes past midnight the answer belongs to the next day. The calculator above adds durations rather than times of day, so the common ones are worked out here.
8:30 AM + 8 h = 4:30 PM
8:30 AM + 9 h = 5:30 PM
7:30 AM + 7.5 h = 3:00 PM
10:30 AM + 8 h = 6:30 PM
8:45 AM + 1.5 h = 10:15 AM
6:00 PM + 9 h = 3:00 AM (next day)
11:30 PM + 8 h = 7:30 AM (next day)
A half hour written as 7.5 or 1.5 behaves the same as 7:30 or 1:30 - it is the same duration, only in decimal - which is why 8:45 AM plus 1.5 hours is 10:15 AM and not 10:30.
Subtracting hours and minutes
Subtracting runs the same arithmetic backwards, borrowing sixty minutes from an hour when the minutes would go below zero. 4 hours minus 15 minutes is 3:45, because the 15 comes out of a borrowed hour rather than off the 4.
4 h − 15 min = 3:45
2 h − 14 min = 1:46
12 h − 1 h 30 min = 10:30
1 h 15 min − 45 min = 0:30
Multiplying hours
To repeat one shift across several days, multiply the decimal hours rather than the hh:mm: 1.5 hours x 5 = 7.5 hours, which is 7:30. The same sum typed as 1.30 x 5 gives 6.50 and is an hour short, because a calculator carries at a hundred and a clock carries at sixty. Convert, multiply, convert back.
Adding up hours worked for a timesheet
To add up the hours you worked, put each day on its own line above and read the total at the bottom - it updates as you type, up to twelve lines. For a payroll export, the same total is shown in decimal hours, which is the format the form usually wants. If what you have written down is clock-in and clock-out times rather than durations, start from the timesheet calculator instead.
Stop retyping your hours
Adding up durations by hand means you first had to write them down. TickTappy times the work as it happens, so the durations are already there and already added up. Free, no account needed.
FAQ
How do you add hours and minutes together?
Convert each time to minutes, add the minutes, then convert back. 7:45 is 465 minutes and 6:30 is 390 minutes, so together they are 855 minutes, which is 14:15. Adding 7.45 and 6.30 as if they were decimals gives 13.75, which is wrong by half an hour.
Can the total be negative?
Yes. If you subtract more time than you have added, the total is shown with a minus sign, for example -1:30. That is useful for flexitime balances, where the question is how far ahead or behind you are.
Can I add up more than 24 hours?
Yes. Totals do not wrap at midnight, so 40 hours shows as 40:00 rather than 16:00. Individual lines can be longer than a day too, so 100:30 is a valid entry.
Can I type decimal hours instead?
Yes, and you can mix the two. 1.5 and 1:30 are both read as ninety minutes, and 1,5 works too for the comma-decimal habit. Whatever you type, the total is shown in both formats.
Is anything saved between visits?
No. The lines exist only while the page is open. Nothing is uploaded and nothing is stored, so reloading brings back the three example lines.
How do I add up my hours worked for the week?
Put each day on its own line and read the total at the bottom, which updates as you type. Five days of 7:30 come to 37:30, shown alongside as 37.50 decimal hours for payroll. The running total beside each line is what tells you which day is wrong when the week does not match your own count.
How do I add hours to a time of day, like 8:30 plus 9 hours?
Add the whole hours to the hour part and leave the minutes alone: 8:30 AM plus 9 hours is 17:30 on a 24-hour clock, which is 5:30 PM. If the total passes midnight the answer belongs to the next day, so 11:30 PM plus 8 hours is 7:30 AM the following morning.
What is an hour and a half after 8:45?
10:15. An hour after 8:45 is 9:45, and another 30 minutes takes it to 10:15. Counting in minutes gives the same answer: 45 plus 90 is 135 minutes past 8:00, which is 2 hours 15 minutes past 8:00.
Can I multiply hours, like 1.5 hours times 5?
Yes, as long as you multiply decimal hours: 1.5 x 5 = 7.5 hours, which is 7:30. Multiplying hh:mm on a calculator does not work - 1:30 typed as 1.30 x 5 gives 6.50, an hour short. Convert to decimal, multiply, then convert the answer back.
How do I subtract minutes from hours, like 2 hours minus 14 minutes?
Borrow sixty minutes from the hour: 2 hours becomes 1 hour and 60 minutes, and 60 - 14 = 46, so the answer is 1:46. On this page, type 2:00 on one line and 0:14 on the next, then press the minus button on that second line.
Related calculators
Also see