Time Duration Calculator
Add or subtract time durations instantly. Enter two time values in hours, minutes, and seconds, choose add or subtract, and get the result.
Hours
Minutes
Seconds
Hours
Minutes
Seconds
2 hr 15 min
Breakdown
1 hr 30 min
+ 45 min
2 hr 15 min
1 hr 30 min + 45 min = 2 hr 15 min
Total seconds = (hours × 3,600) + (minutes × 60) + seconds
The calculator converts each time value to seconds, performs the addition or subtraction, then converts back to a human-readable format. Minutes and seconds cap at their maximum values (59), with overflow rolling into the next unit.
Example: 2h 45m + 1h 30m → (9900 + 5400) seconds = 15,300 seconds = 4h 15m.
What is 1 hour 45 minutes minus 50 minutes?
1h 45m − 50m = 55 minutes. Convert both to minutes: 105 − 50 = 55 minutes, which is less than an hour, so the result is 55 minutes (or 0 hr 55 min 0 sec).
How do I calculate 8 hours minus 9 hours?
The result will be negative: 8h − 9h = −1 hour (or −1 hr 0 min 0 sec). The calculator handles negative durations correctly.
Can I add more than two durations?
This version handles two durations at a time. To add multiple durations, use the calculator twice: add A + B, then add the result to C.
Does this handle days or weeks?
No — this calculator works with hours, minutes, and seconds within a single day. For day-spanning calculations, convert to total hours or use a date calculator.