Add Times Calculator
Add Times Calculator works out Duration in hours and Duration in minutes from Durations, A two-part duration like 3:45 means and Start time. The default figures on this page give duration in hours of 4.2500 h; change any entry and the result, the working and the sources update together.
Your figures
Updates as you typeHow this is worked out
2 steps
- Total of 2 duration(s): 1:30:00 + 2:45:00 = 4:15:00.
- 255 minutes total = 4.25 hours (60 s = 1 min, 60 min = 1 h).
Each durationtable
| index | clock | minutes | hours |
|---|---|---|---|
| 1 | 1:30:00 | 90 | 1.5 |
| 2 | 2:45:00 | 165 | 2.75 |
Its 10 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
3 sources
What the Add Times Calculator calculates
Elapsed time between two clock times, including overnight and multi-day spans, adding or subtracting hours, minutes and seconds from a time, totalling a list of durations such as a playlist or a set of videos, halving or splitting a duration, and rescaling a runtime for playback speed.
How to use this Add Times Calculator
Enter Durations, A two-part duration like 3:45 means, Start time and Start date (optional). Duration in hours updates as you type. Change one figure at a time to see what drives the result.
How the result is worked out
Open “How this is worked out” beside the result for the step-by-step calculation behind Duration in hours, Duration in minutes and Duration in seconds.
The method follows ISO 8601-1:2019, Date and time - Representations for information interchange, clauses 5.3 and 5.5, BIPM SI Brochure, 9th edition, Table 8 (non-SI units accepted for use with the SI) and US Department of Labor, Fact Sheet #22: Hours Worked Under the FLSA.
What you can compare
Change one input at a time to see how it affects Duration in hours, Duration in minutes and Duration in seconds. The inputs you can vary are Durations, A two-part duration like 3:45 means, Start time, Start date (optional) and End date (optional).
Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.
See something wrong? Report a problem with this calculator
Frequently asked questions
Can a time calculator add time?
Elapsed time between two clock times, including overnight and multi-day spans, adding or subtracting hours, minutes and seconds from a time, totalling a list of durations such as a playlist or a set of videos. Put your own figures in above and the working updates beside the result. For scale, the default figures on this page give 4.2500 h.
Can you provide a calculator for adding minutes?
It needs Durations, A two-part duration like 3:45 means, Start time, Start date (optional) and End date (optional). Nothing else is required, and the figures stay in your browser.
How to put time on a calculator?
Elapsed time between two clock times, including overnight and multi-day spans, adding or subtracting hours, minutes and seconds from a time, totalling a list of durations such as a playlist or a set of videos. Open “How this is worked out” beside the result to see each step for your own figures.
How to add and subtract time?
The result gives Duration in hours, Duration in minutes, Duration in seconds, Whole days, Hours part and Minutes part, each labelled with its unit so the figure can be read on its own.
What information do I need for the Add Times Calculator?
You need Durations, A two-part duration like 3:45 means, Start time, Start date (optional) and End date (optional). The page opens with default figures that give duration in hours of 4.2500 h, so you can see the scale before entering your own.
What does this Add Times Calculator show?
It shows Duration in hours, Duration in minutes, Duration in seconds, Whole days, Hours part, Minutes part, Seconds part and Duration as h:mm, with the working and any warnings for your entries.