Hours and minutes calculator
Add or subtract multiple durations and compare the result as signed HH:MM, decimal hours, total minutes, or 24-hour days.
Total multiple hours and minutes
Use whole hours from 0 to 1,000,000 and whole minutes from 0 to 59 in each row. A negative total is valid.
| Expression | Signed HH:MM | Decimal hours | Total minutes | Days |
|---|---|---|---|---|
| 1:30 + 0:45 | 2:15 | 2.25 | 135 | Under 1 day |
| 8:30 + 7:45 - 0:30 | 15:45 | 15.75 | 945 | Under 1 day |
| 1:15 - 2:00 | -0:45 | -0.75 | -45 | Under 1 day |
| 24:00 + 3:30 | 27:30 | 27.50 | 1,650 | 1 day, 3:30 |
| 100:00 - 25:15 | 74:45 | 74.75 | 4,485 | 3 days, 2:45 |
The minus sign applies to the complete result. For example, -0:45 means the subtracted durations exceed the added durations by 45 minutes; it is not a clock time before midnight.
How to add hours and minutes
Convert every duration to minutes, add the minute values, then divide the total by 60. The whole-number quotient is the hour portion and the remainder is the minute portion. For 1:50 + 2:25, the calculation is 110 + 145 = 255 minutes, which becomes 4:15.
The calculator performs this conversion for every row before applying the selected add or subtract operation. That avoids manually carrying 60 minutes into the hours column and keeps the total-minute result available for checking.
How subtraction and negative time totals work
A subtract row reverses the sign of that duration. For 5:00 - 1:45, subtract 105 minutes from 300 minutes to get 195 minutes, or 3:15. You can mix add and subtract rows in any order because the final sum uses signed whole minutes.
When the subtracted duration is larger, the result is negative. For 1:15 - 2:00, the calculator returns -0:45, -0.75 decimal hours, and -45 total minutes. A negative duration is mathematically valid even though it is not a time of day.
Convert totals longer than 24 hours into days
Duration hours do not roll over at midnight. A 27:30 total remains 27:30 in the primary result and is also shown as 1 day, 3:30 when one day is defined as exactly 24 hours. This is useful for project effort, media run time, leave balances, and other elapsed-time totals.
The day breakdown is not a working-day conversion. It does not assume an eight-hour workday or remove weekends. Use the working days calculator for calendar dates, and divide by the relevant scheduled hours separately when estimating workdays from a duration.
Input limits and rounding
Each row accepts whole hours from 0 to 1,000,000 and whole minutes from 0 to 59. Add up to 50 rows. A minute entry of 60 should instead be entered as one additional hour and zero minutes, while fractional minutes should be rounded or converted from seconds before entry.
The HH:MM and total-minute results retain whole-minute precision. Decimal hours are shown to two places, so thirds and other repeating fractions are rounded only for display. Keep the total-minute value when another calculation needs the exact result.
Duration math is different from clock subtraction
This page expects elapsed durations such as 2 hours 30 minutes. It does not interpret 08:30 or 17:00 as clock readings, infer overnight work, or deduct an unpaid break. Use the work hours calculator when your source values are clock-in and clock-out times.
The calculator also does not apply payroll rounding, overtime thresholds, billing increments, or time-zone changes. Apply those rules to the underlying records before or after the duration arithmetic as the relevant policy requires.