About the Time Calculator
Time uses base 60, which makes mental math surprisingly error-prone. This time calculator does it for you. ① Add or subtract time handles sums like 1 h 30 min + 2 h 45 min, or clock questions like “what time is it 3 hours after 10:30 PM?”. ② Add up a list of times totals study sessions, video lengths, lap times or billable hours, one per line. ③ Hours worked takes a start and end time, subtracts your unpaid break and shows the hours over 8 and the hours worked at night, plus a weekly total for your timesheet.
How to use
- In ①, enter hours, minutes and seconds and choose Add or Subtract. Minutes over 60 carry over automatically.
- To find what time something ends, tick First value is a clock time. Results past midnight are marked “Next day”.
- In ②, type one duration per line to get the total and the average. The list is saved in this browser.
- In ③, enter your start and end time and choose the break to get the hours worked and the weekly total.
Converting minutes to decimal hours
Timesheets and payroll often need hours as a decimal number. Divide the minutes by 60: decimal hours = hours + minutes ÷ 60.
| h:mm | Decimal hours |
|---|---|
| 0:15 | 0.25 |
| 0:30 | 0.5 |
| 0:45 | 0.75 |
| 1:20 | about 1.33 |
| 7:40 | about 7.67 |
Section ① shows the decimal hours under every result.
Breaks, overtime and night hours
The hours-worked calculator subtracts the break you choose from the time between start and end. “Over 8 hours” shows how much of the day goes beyond 8 working hours, and “Night” counts the minutes between 10 PM and 6 AM. Whether those hours earn overtime or a night premium depends on where you work: in the US, for example, federal law requires overtime pay after 40 hours in a workweek, while some states also have daily overtime rules. Check your contract or local labor law.
FAQ
What if the end time is earlier than the start time?
The calculator assumes you worked past midnight and counts the end time on the next day. For example, 10:00 PM to 7:00 AM is 9 hours on site.
Which formats can I use in the list?
1:30 (1 hour 30 minutes), 1:30:15 (h:mm:ss), 2h 15m, 90 min, 45 s, 1.5h and 2 hours 30 minutes all work. A plain number is read as minutes, and a line starting with − is subtracted.
Can the total go over 24 hours?
Yes. Totals are not wrapped into days; they are shown as total hours, such as 30:15:00.
How do I subtract a time from a clock time?
Tick “First value is a clock time”, enter the clock time first and the duration second, then choose Subtract. For example, 1:00 − 2 h gives 11:00 PM on the previous day.