Time Duration Calculator
Calculate the duration between two times — for meetings, work sessions, events, and time tracking.
Get a duration in three fields or less
Enter a start and end time, optionally subtract a break, and read the result in whichever format you need: decimal, HH:MM, total minutes, or a plain-English “8 hours 30 minutes”.
Use the native time field. 9:00 AM, 14:30, 11:45 PM — the input accepts any valid time.
If your end is earlier than your start (e.g., 23:00 → 07:00), the tool treats it as an overnight shift.
Subtract an unpaid lunch or break in minutes — the running total updates instantly.
Copy the decimal value for payroll, the HH:MM for schedules, or the total minutes for logs.
How to calculate time duration by hand
The calculator runs this math for you. If you ever want to check it manually, here’s the same logic written out.
- 1Convert both times to 24-hour format. 9:00 AM becomes 09:00 and 5:30 PM becomes 17:30.
- 2Subtract start from end. 17:30 − 09:00 = 8h 30m.
- 3Subtract break minutes. 8h 30m − 30m = 8h 0m.
- 4Convert to decimal. 8 + 0÷60 = 8.00 decimal hours.
Common time duration calculations
A handful of quick reference rows — the patterns most people end up computing repeatedly.
| Scenario | Start | End | Duration (HH:MM) | Decimal |
|---|---|---|---|---|
| Full workday | 9:00 AM | 5:00 PM | 08:00 | 8.00 |
| Workday + 30m lunch | 9:00 AM | 5:30 PM | 08:00 | 8.00 |
| Workday + 1h lunch | 8:00 AM | 5:00 PM | 08:00 | 8.00 |
| Half-day | 9:00 AM | 1:00 PM | 04:00 | 4.00 |
| Short meeting | 10:00 AM | 10:45 AM | 00:45 | 0.75 |
| Long meeting | 2:00 PM | 3:30 PM | 01:30 | 1.50 |
| Overnight shift | 11:00 PM | 7:00 AM | 08:00 | 8.00 |
| Night shift | 10:00 PM | 6:30 AM | 08:30 | 8.50 |
| Long travel day | 6:45 AM | 8:15 PM | 13:30 | 13.50 |
Rows assume breaks are already subtracted where noted. Use the calculator above to tweak any of these.
When to use a time duration calculator
Any time you need to go from two clock times to a single duration — without opening a spreadsheet.
- • Timesheet entries
- • Meeting lengths
- • Project time
- • Billable hours
- • Event duration
- • Meeting schedules
- • Travel time
- • Task estimates
- • Workout duration
- • Study sessions
- • Sleep hours
- • Cooking times
- • Hours worked
- • Overtime triggers
- • Shift lengths
- • Hourly invoices
Handling overnight and multi-day durations
The calculator handles the two scenarios people most often trip on: shifts that cross midnight, and events that span several calendar days.
Overnight shifts
If the end time is earlier than the start time (like 23:00 → 07:00), the calculator treats the end as the next day and adds 24 hours. Result: 8 hours.
Multi-day durations
For events longer than one day, check “Spans multiple days” and enter both a start and end date. Example: Monday 9:00 AM to Wednesday 5:00 PM = 2 days, 8 hours (56 total hours).
Time duration, answered
Subtract the start time from the end time. For example, 5:00 PM − 9:00 AM = 8 hours. This calculator does the conversion to 24-hour format, math, and break subtraction automatically.
Calculate the total duration between start and end, then subtract break minutes. Example: 8 hours 30 minutes total − 30 minute lunch break = 8 hours (or 8.00 decimal hours).
The calculator assumes the end time is on the next day. For example, 11:00 PM to 7:00 AM counts as 8 hours (an overnight shift). If your shift actually spans multiple days, check the “Spans multiple days” box to use explicit start/end dates.
Yes. Check “Spans multiple days” and enter both a start date and an end date. The tool will add the day offset to the total duration and report days + hours + minutes separately.
Divide the minutes by 60 and add to the hours. Example: 8 hours 30 minutes = 8 + (30 ÷ 60) = 8.5 decimal hours. The calculator shows this automatically on the decimal tile.
Elapsed time is the duration between a start moment and an end moment. It is the same thing as “time duration” — this calculator works for either term.
Yes. Enter 23:00 as the start and 07:00 as the end with “Spans multiple days” unchecked — the tool will detect the overnight and return 8 hours.
Yes. No account, no signup, and all math happens in your browser — the times you enter never leave your device.
More time & payroll calculators
Already have a duration? These tools handle the next step.
Hours to Decimal
Convert HH:MM into decimal hours for payroll.
Open →Decimal to Hours
Turn decimal hours back into readable HH:MM.
Open →Timesheet
Add up a full week with breaks and overtime split.
Open →Minutes to Decimal
Quick convert stopwatch minutes to decimal hours.
Open →Break Time
Required breaks by state based on hours worked.
Open →