Duration
The measurable length of time that something continues or exists between a start and end point.
Definition
Time Duration is the measurable length of time that something continues or exists between a specific start point and end point.
Why It Matters
Unlike money, distance, or weight—which operate on a base-10 decimal system—time operates on a base-60 system (60 seconds in a minute, 60 minutes in an hour). This makes calculating the duration between two times incredibly confusing, as standard mathematical subtraction does not work.
Practical Example
The Base-60 Trap
Imagine you start working at 8:45 AM and finish at 10:15 AM. How long did you work?
If you try to subtract standard decimals (10.15 - 8.45), you get 1.70. This is completely wrong.
To calculate time duration manually, you must count the minutes up to the nearest hour:
- From 8:45 AM to 9:00 AM = 15 minutes.
- From 9:00 AM to 10:00 AM = 1 hour.
- From 10:00 AM to 10:15 AM = 15 minutes.
- Total = 1 hour and 30 minutes.
If you are a freelancer or contractor, calculating this by hand every day is a recipe for billing errors. Instead, use our Time Duration Calculator to get perfect hour and minute breakdowns instantly.
Frequently Asked Questions
Why is calculating duration tricky?
Because time operates on a base-60 system (60 minutes in an hour) rather than a base-10 system, so standard decimal subtraction doesn't work.
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