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⏰ Time Calculator

Add or subtract hours and minutes. Perfect for calculating work shifts, travel time, or task duration.

Enter Your Values

Enter hours for first time
Enter minutes for first time
Enter hours for second time
Enter minutes for second time

When to Add vs Subtract Time — and Why It Matters

Time addition is used when you want to find the total duration of multiple time blocks. If you worked 3 hours 45 minutes in the morning and 2 hours 30 minutes in the afternoon, the total is 6 hours 15 minutes. Adding time must respect the 60-minute clock — 45 minutes + 30 minutes = 75 minutes = 1 hour 15 minutes, which carries over into the hours column.

Time subtraction finds the elapsed time between two points, or the remainder after removing a duration from a total. If you had 8 hours of work time and used 5 hours 20 minutes on tasks, you have 2 hours 40 minutes remaining. When subtracting, borrowing from the hours column works like borrowing from the tens column in decimal subtraction: if your minutes are insufficient, borrow 1 hour (60 minutes) from the hours column.

Common use cases: calculating total shift hours from individual sessions, finding remaining time in a project given time already spent, working out how long a journey took from start and end times, and tracking billable hours across a day. For the specific use case of calculating hours between a start and end clock time, the Hours Calculator on CalForge is more direct.

Converting the result: the output of this calculator is in hours and minutes. For billing purposes, you may need to convert minutes to decimal hours. To convert minutes to a decimal fraction: divide by 60. So 45 minutes = 0.75 hours. 30 minutes = 0.5 hours. 20 minutes = 0.333 hours. Bill for 3 hours 45 minutes at $200/hour: 3.75 × $200 = $750.

For multi-day time calculations or date arithmetic, use the Days Between Dates Calculator on CalForge.

How to Add and Subtract Time

Adding or subtracting time requires handling 60-based arithmetic (minutes and seconds go from 0-59, not 0-99). When adding, carry over to the next unit when the value reaches 60. When subtracting, borrow from the next higher unit when going negative.

Time addition and subtraction is used for scheduling, timesheet calculations, flight times, countdown timers, and calculating how long between two points in time within a single day.

Frequently Asked Questions

How do I add hours and minutes together? +
Add the minutes first. If the total exceeds 60, subtract 60 and carry 1 to the hours. Then add the hours plus any carried value. Example: 2h 45m + 1h 30m = (45+30=75min → 60=1h, 15min remaining) = 4h 15m.
How do I convert decimal hours to hours and minutes? +
Multiply the decimal portion by 60. Example: 3.75 hours = 3 hours + (0.75 × 60) = 3 hours 45 minutes. 2.33 hours = 2 hours + (0.33 × 60) = 2 hours 20 minutes.
What is the easiest way to calculate hours between two times? +
Convert both times to minutes since midnight. Subtract the earlier from the later. Divide by 60 for hours. Example: 9:15am to 5:45pm = (17×60+45) − (9×60+15) = 1065 − 555 = 510 minutes = 8.5 hours.