Omni Calculator logo

Hours Calculator

Created by Rita Rain
Reviewed by Dominik Czernia, PhD and Jack Bowater
Last updated: Jan 18, 2024

Pleasure and action make the hours seem short - when counting time, it's better not to trust your intuition - use the hours calculator instead.

This Omni application includes:

  • A job hours calculator ( payroll hours calculator);
  • An add hours calculator;
  • An hour from now calculator;
  • An hours converter (hours to days calculator, and the like); and
  • An hour difference calculator.

And there is no need to race against time, we have our time calculator, just so you can take it easy.

Add hours calculator

If you'd like to add hours, choose the first option in the first field of the hours calculator. Input your hours in the fields below, and the sum will show at the bottom. You can input negative values (to subtract hours) and change the units of time.

Example - If you know this week you worked 3 h on Monday, 6 h 45 min on Tuesday, and 7 h 55 min on Friday, you can change the units of first three fields of this add hours calculator to "hours minutes", input your numbers and get the result in hours for your payroll.

Hour converter

If you choose the second option in the first field of the hours calculator, you'll see an hours converter. Choose the unit of time and the target unit first, and input the number.

Example - If you'd like to know how many days and hours are in 235 h, leave the default setting as it is and input "235" in the second field. You should see that it equals 9 days 19 hours.

You can use this part as a minutes to hours calculator, hours to days calculator, or other time converters you need.

If you are unsure of units of time, then be sure to check out OMNI's time unit converter. It is sure to make your life easy.

Calculate hours between two times

Let's say you've worked from 9:45 am to 4:25 pm and want to check how many hours that was. In that case, choose the third option in the first field of the hours calculator. In the Start time field, enter 9 hrs 45 min. In the End time field, we'll need a 24-hour format - we'll get it by adding 12 hours to the PM time. In this case, it would be 4 h 25 min + 12 h = 16 h 25 min. Once you enter the number, you'll see the result - you worked for 6 h 40 min.

We also have a date duration calculator that lets you estimate the number of days between two dates. Be sure to check it out, you never know when you might need it.

Time card hour calculator

If you want to ask "How many hours did I work, calculator?", choose the fourth functionality - the weekly hours calculator. Then choose if your break is always the same length and whether you work on weekends. By default, it's an 8-hour work day calculator running from 8 am to 5 pm with a 1-hour unpaid lunch. To change the hours, click the calendar icon and choose your start and end time. Alternatively, you can select the default times and type in work times in the same format.

In the advanced mode (below the weekly hours calculator), you can set up your usual and overtime hourly rate. Once you do this, the job hour calculator will output your weekly pay.

Hours from now calculator

If you'd like to find what time it'll be in x hours, choose the fifth option in the hours calculator. Input the number of hours (or another time unit) in the first input field. If you want hours from now, leave the default date; otherwise, you need to set it yourself. The last field will output the end date (will tell you what time/date it will be some time from now).


How to calculate hours worked?

  1. Convert start time and end time to the 24-hour format by adding 12 hours to the PM times. E.g. 4:30 PM = 4:30 + 12:00 = 16:30.

  2. Subtract the start time from the end time. E.g., 16:30 - 9:00 = 7:30.

  3. If your working time included an unpaid break, subtract it from the time obtained in the previous step. E.g., 7:30 - 0:30 = 7:00.

  4. Repeat steps 1-3 for all days you want to include and sum them up. E.g., if you'd like to find your weekly hours and your schedule is the same on each day:

    7 + 7 + 7 + 7 + 7 = 35.

How many hours is part time (a day)?

A part-time job requires less than 8 hours a day. In the US, there's no clear legal definition of a part-time job. Part-time means less than full-time, in practice, less than 35 hours per week, and less than 7 hours per day. The exact time depends on an agreement and can vary.

How to calculate hours worked per week?

  1. Convert all start and end times to the 24-hour format by adding 12 hours to the PM times. E.g. 7:30 PM = 7:30 + 12:00 = 19:30.

  2. For each day of the week, subtract the start time from the end time. E.g., 19:30 - 12:00 = 7:30.

  3. If your working time included an unpaid break, subtract it from the time obtained in the previous step. E.g., 7:30 - 0:30 = 7:00.

  4. Add the hours obtained for each day of the week.

How to calculate overtime hours?

  1. Determine after how many hours overtime starts. Usually, overtime is the time exceeding 40 hours a week.

  2. Calculate how many hours you've worked in a given week.

  3. Subtract 40 hours from your weekly hours to find how long your overtime is.

Rita Rain
Related calculators
I want to
find the hours between two times
Start time
End time
Check out 32 similar time and date calculators ⏳
8-hour shiftAdd timeAge… 29 more
People also viewed…

Christmas tree

Welcome to the Christmas tree calculator, where you will find out how to decorate your Christmas tree in the best way. Take a look at the perfect Christmas tree formula prepared by math professors and improved by physicists. Plan in advance how many lights and decorations you'll need!

Helium balloons

Wondering how many helium balloons it would take to lift you up in the air? Try this helium balloons calculator! 🎈


The RPM calculator helps you understand RPM (revolutions per minute) and compute the relationship between the speed of a vehicle and the RPM of its engine.

TV alternatives

This calculator shows how you could use your TV time in a more productive way.
Copyright by Omni Calculator sp. z o.o.
Privacy, Cookies & Terms of Service