Hours Calculator
Are you looking to calculate the hours difference between two important hours? No worries. Simply input your start hour and end hour into the form below, and the total hours will be calculated for you.
Preview with current fields: 7:30 (7.50 decimal hours). Click Calculate to lock the result.
How to use the hours calculator?
Change the start and end times, optionally add break minutes, then click Calculate. The tool returns hours worked in hours and minutes, plus decimal hours. That format is handy for time card math.
For example, set start to 9:30 and end to 17:00, then calculate. You get both clock-style hours and minutes and the decimal equivalent.
The start time is when timing begins, and the end time is when it stops. If the period crosses midnight, end can be earlier on the clock than start and the calculator treats it as an overnight shift. For multi-day spans, use the between-dates form below.
How do you convert digital time to decimal time?
If you worked 8:30 (8 hours and 30 minutes), the decimal form is 8.50. Divide minutes by 60: 30 / 60 = 0.5 hours. Then 8 + 0.5 = 8.5 decimal hours.
To go the other way, take the decimal part and multiply by 60. For 9.25 hours, 0.25 × 60 = 15 minutes, so the clock form is 9 hours and 15 minutes.
Hours Between Two Dates
If work hours span more than one calendar day, use this form to measure the full duration without hand math.
How to use the time between dates calculator?
When a shift crosses days, enter both dates and clock times, then Calculate. You get a summary in hours and minutes plus decimal hours.
Tip: also see the days calculator when you need day counts rather than hours.
Calculate work hours with lunch
Enter the start and end of your workday and the break length in minutes. The calculator subtracts the break and reports paid hours in hh:mm and decimal form. A common example is how many hours is 8am to 5pm with lunch: change the fields above for an instant answer.
Example: 8:30 AM to 5:00 PM with a 30-minute break is 8 hours of work time. For weekly totals by day, use the time card calculator.
How to calculate hours worked manually?
- Convert start and end to 24-hour time. AM hours stay as-is; add 12 for PM hours (8:30 AM to 5 PM becomes 8:30 and 17:00).
- Convert minutes to decimal hours by dividing by 60 (30 / 60 = 0.5, so 8:30 becomes 8.50).
- Subtract start from end (17 − 8.5 = 8.5 hours).
- Subtract breaks in decimal hours (30 minutes = 0.5). Then 8.5 − 0.5 = 8 hours worked.
Tip: when you need to add hours onto a clock time, check the time calculator.
How many hours?
The table below lists common start and end pairs. It does not deduct unpaid breaks.
| Start - End Time | Time Between |
|---|---|
| 7AM to 5PM | 10:00 |
| 7:30AM to 4:00PM | 8:30 |
| 7:30AM to 4:30PM | 9:00 |
| 7:30AM to 3:30PM | 8:00 |
| 8AM to 4PM | 8:00 |
| 8:30AM to 4:30PM | 8:00 |
| 8:30AM to 5PM | 8:30 |
| 8AM to 5PM | 9:00 |
| 8:30AM to 5:30PM | 9:00 |
| 8AM to 6PM | 10:00 |
| 8AM to 8PM | 12:00 |
| 9AM to 4PM | 7:00 |
| 9AM to 5PM | 8:00 |
| 9AM to 5:30PM | 8:30 |
What is an hour?
An hour equals 60 minutes, or 3,600 seconds. There are 24 hours in a day. Common conversions:
| Time unit | Hours |
|---|---|
| a day | 24 |
| a week | 168 |
| a month (28 / 29 / 30 / 31 days) | 672 / 696 / 720 / 744 |
| a year (365 / 366 days) | 8,760 / 8,784 |
What is the difference between a 12-hour clock vs. 24-hour clock?
A 12-hour clock splits the day into AM and PM periods. The same hour number (for example 3:00) appears twice, once in the morning and once in the afternoon.
A 24-hour clock (often called military time) runs from 00:00 to 23:59, so each hour number is unique. 03:00 is 3:00 AM and 15:00 is 3:00 PM. To convert PM times to 24-hour form, add 12 to the hour (except 12 PM stays 12:00).
How many hours is part-time?
Definitions vary by employer and location. In many workplaces, part-time is under about 35 to 40 hours per week. Common ranges include about 20 to 29 hours, or 30 to 34 hours.
Under the Affordable Care Act in the United States, full-time status for certain coverage rules averages 30 hours or more per week (or 130 hours or more per month). Many employers still treat 35 to 40 hours as a full-time schedule.
Common hours questions
How many hours is 8am to 4pm with 30 minute lunch?
From 8am to 4pm is 8 hours. Subtract 30 minutes and you get 7 hours 30 minutes, or 7.5 decimal hours.
How many hours is 8am to 5pm with lunch?
From 8am to 5pm is 9 hours. With a 30-minute lunch, that is 8 hours 30 minutes, or 8.5 decimal hours.
What time is 8 hours from 9:30?
Adding 8 hours to 9:30 AM lands at 5:30 PM. You can also use the hours from now calculator for forward offsets from the current clock.
How to calculate overtime?
Overtime is often paid at 1.5 times the regular hourly rate after a weekly threshold such as 40 hours. Measure total hours for the pay period, subtract regular hours, multiply overtime hours by 1.5 times the base rate, then add regular pay.
Example: $20/hour base, 45 hours worked, 40-hour threshold. Overtime hours = 5. Overtime rate = $30/hour. Overtime pay = $150. Regular pay = $800. Total = $950.