Examples
Adding up clip lengths
An editor has clips of 12 min 40 s, 8 min 55 s and 21 min 30 s, and must cut 4 min 15 s. Enter the three clips, then a fourth row switched to −.
- Seconds: 40 + 55 + 30 − 15 = 110 s, which is 1 min 50 s.
- Minutes: 12 + 8 + 21 − 4 = 37, plus the 1 carried over = 38.
- Total: 38 min 50 s.
When will it be done?
A slow cooker starts at 9:15 PM and needs 10 hours 30 minutes. In the Clock time ± tab the answer is 7:45 AM, marked “+1 day” because it passes midnight.
How the total is worked out
Every row is turned into seconds, the rows are added (or subtracted), and the total is split back into days, hours, minutes and seconds. That’s why 90 minutes shows as 1 hour 30 minutes. Decimals work in any box, so 1.5 hours is fine.
For clock times, the duration is added to the start time and wrapped around midnight, with the number of days crossed shown as a tag. This mode treats times as wall-clock times and ignores daylight-saving changes; for those, use the time duration calculator with dates.