Add or subtract time units
Combine two durations in seconds, minutes, hours, days or weeks using the shared time-unit converter.
Formula
Convert both durations to seconds; add or subtract, then convert the result.
First duration: 2 h · Second duration: 0.5 h · Seconds ≈ (2 h × 3,600 s/h) + (0.5 h × 3,600 s/h) · Minutes ≈ (9,000) ÷ 60 · Hours ≈ (9,000) ÷ 3600 · Days ≈ (9,000) ÷ 86400
How to use
- Enter each duration and its unit.
- Choose addition or subtraction.
- Read the signed result in several time units.
Examples
- 2 hours + 30 minutes = 150 minutes = 2.5 hours.
Frequently asked questions
Does one day always mean 24 hours?
Yes. These are fixed durations, not calendar dates.
Why can the result be negative?
Subtraction keeps the sign when the second duration is larger.
Can I use months or years?
No. Their calendar lengths vary; only fixed time units are supported.
Sources
Updated: