How to use the hours calculator
Type a start time and an end time and the answer appears instantly — in hours and minutes, in decimal hours and in total minutes. There is no calculate button to press and nothing to install.
- Fast typing: 9, 930, 9:30 and 09:30 all work. Add “a” or “p” for AM or PM (for example
5p), or tap the AM/PM button. Switch to 24-hour mode to type times like1730. - Smart AM/PM: until you tap the button yourself, the end time takes whichever AM/PM gives the shorter span. From 9:00 AM, typing “5” means 5:00 PM; from 10:00 PM, typing “6” means 6:00 AM.
- Overnight shifts: if the end time is earlier than the start time, the calculator assumes it is on the next day. 10:00 PM to 6:00 AM is 8 hours.
- Breaks: enter an unpaid break in minutes and it is subtracted from the result.
- Longer spans: turn on Use dates to count hours across several days, for example Monday 9:00 AM to Wednesday 5:00 PM (56 hours).
- Totals: press Add to list below to collect several results and add them up, then enter an hourly rate to see the pay.
How to calculate hours between two times by hand
Convert both times to 24-hour time, then subtract the minutes and the hours separately. If the end minutes are smaller than the start minutes, borrow one hour (60 minutes) from the end hour.
Example: 8:45 AM to 5:15 PM becomes 08:45 to 17:15. Minutes: 15 − 45 does not work, so borrow an hour: 75 − 45 = 30 minutes, and the end hour drops from 17 to 16. Hours: 16 − 8 = 8. The answer is 8 hours 30 minutes, or 8.5 hours.
Overnight example: 10:30 PM to 7:00 AM becomes 22:30 to 07:00. Because the end is earlier, add 24 hours to it: 31:00 − 22:30 = 8 hours 30 minutes.
Converting minutes to decimal hours
Payroll systems, timesheets and invoices usually want hours as a decimal number. To convert, divide the minutes by 60 and add the result to the whole hours: 7 hours 45 minutes = 7 + 45 ÷ 60 = 7.75 hours. To go back, multiply the decimal part by 60: 0.75 × 60 = 45 minutes.
A common mistake is to read 7.45 hours as 7 hours 45 minutes. It is actually 7 hours and 27 minutes (0.45 × 60 = 27). The converter above and the chart of 1–60 minutes make this quick.
- 6 minutes = 0.1 hour
- 15 minutes = 0.25 hour
- 20 minutes = 0.33 hour (0.333…)
- 30 minutes = 0.5 hour
- 40 minutes = 0.67 hour (0.666…)
- 45 minutes = 0.75 hour
Adding and subtracting hours and minutes
When you add times, minutes carry over at 60, not 100: 3:45 + 2:30 = 6:15, not 5:75. The add/subtract list does this for you. Each line accepts hours:minutes (1:30), decimal hours (1.5) or units (1h 30m, 90m), so you can mix formats copied from different apps.
Tap the + button on a line to turn it into a subtraction — handy for taking out an unpaid break or time you already billed. If you enter an hourly rate, the pay is calculated from the exact total, not from a rounded number.
12-hour vs 24-hour (military) time
In 24-hour time the day runs from 00:00 to 23:59. For afternoon and evening hours from 1 PM to 11 PM, add 12 to the hour; for 12 AM, use 00. The calculator accepts both styles in either mode.
- 12:00 AM (midnight) = 00:00
- 6:30 AM = 06:30
- 12:00 PM (noon) = 12:00
- 1:00 PM = 13:00
- 6:30 PM = 18:30
- 11:59 PM = 23:59
FAQ
How many hours is 9 AM to 5 PM?
Eight hours. If you take an unpaid 30-minute lunch break, the paid time is 7 hours 30 minutes, or 7.5 hours.
How do I calculate hours worked with a lunch break?
Find the time between clocking in and clocking out, then subtract the unpaid break. For example, 8:00 AM to 4:30 PM is 8 hours 30 minutes; minus a 30-minute lunch that is 8 hours. Enter the break in the Unpaid break box and the calculator does the subtraction. For a full week, use the Time Card Calculator.
What is 8 hours and 20 minutes as a decimal?
8.33 hours. Divide 20 minutes by 60 to get 0.333…, then add it to the 8 whole hours. The chart above lists every minute from 1 to 60.
Does the calculator handle overnight shifts?
Yes. If the end time is earlier than the start time, it is counted as the next day, so 11:00 PM to 7:30 AM gives 8 hours 30 minutes. For spans longer than 24 hours, turn on Use dates.
How do I calculate the hours between two dates?
Turn on Use dates, pick a start date and an end date and enter the times. Monday 9:00 AM to Wednesday 5:00 PM, for example, is 56 hours.
Is 12:00 AM midnight or noon?
In the usual convention 12:00 AM is midnight (the start of the day) and 12:00 PM is noon. Because the labels confuse many people, you can switch to 24-hour mode and type 00:00 for midnight and 12:00 for noon.
Is anything I type saved or sent anywhere?
Your last inputs are saved only in this browser (local storage) so they are still there next time. Nothing is sent to a server.