Time Duration Calculator
Calculate elapsed hours and minutes between two clock times, with an option for durations that pass midnight.
How it works
Convert each clock time to minutes after midnight. Subtract the start from the end; if the interval passes midnight, add 24 hours before calculating the elapsed time.
Formula / calculation method
Convert each clock time to minutes after midnight.duration minutes = end minutes − start minutesIf the interval crosses midnight, add 1,440 minutes to the end time before subtracting.
Worked examples
- 09:15 to 11:45 is 2 hours 30 minutes.
- 22:30 to 01:00 with next-day enabled is 2 hours 30 minutes.
When this tool helps
Useful for shifts, meetings, study sessions, travel segments, appointments, workouts, timesheets, and overnight intervals.
Related calculations: age calculator and days between dates.
Browse this topic: Education, Age & Date Calculators · GPA, Grade & Date Calculation Guide.
Quick reference
| Input | Result |
|---|---|
| 09:15 → 11:45 | 2 h 30 min |
| 22:30 → 01:00 next day | 2 h 30 min |
| 08:00 → 16:00 | 8 h |
Accuracy and definitions
This tool calculates clock-time duration within a 24-hour or overnight interval. It does not model daylight-saving transitions or time-zone changes because no date or location is supplied.
Methodology & verification
- Method
- Convert each clock time to minutes after midnight. Subtract the start from the end; if the interval passes midnight, add 24 hours before calculating the elapsed time.
- Verification
- The displayed formula is cross-checked against Solveberry regression cases before release. Calculator inputs and results stay in the browser.
- Last reviewed
- 2026-08-19
Results are calculated locally in your browser. Optional analytics do not include calculator input values or results.
Common questions
What if the end time is earlier than the start time?
Enable the next-day option when the interval crosses midnight.
Does this handle time zones?
No. Both times are treated as being on the same local clock.
How does the calculator handle calendar boundaries?
The method is shown on the page. Date calculations use explicit calendar dates rather than assuming every month has the same length.
Does this replace an official deadline or age determination?
No. For legal, eligibility or contractual decisions, verify the result against the rule or authority that defines the relevant date or age.