We hope this time calculator will save you some headache by making the basic operations on time easier. It is quite universal to have problems with time - from time to time, we:

Race against time, live on borrowed time, work overtime, give someone a rough time, hardly have time to breath, dance out of time, kill time, and waste the hours in an offhand way.

How to manage all these time problems?

The time and date calculator lets you subtract time (find time difference), multiply time, divide time, add time, and calculate the time between dates. It also incorporates a time to time calculator (you can check time duration, e.g. how many days and hours passed from 2.03.2010 11:00 am to 3.04.2010 6:30 pm). In the text, you'll find instruction on how to use each part of the calculator, and how to calculate time manually.

If you still haven't found the time calculator you're looking for, check out our:

Add time calculator

To use the add time calculator:

  1. Choose the unit of your value and input it.
  2. Proceed with all your numbers. You can enter up to 20 - new rows will appear as you fill in the last field. The values can have different units.
  3. Choose the unit in which you want the result to be in. You'll find it in the last field of the time calculator.


You've written down your tasks for the evening and want to know how long they will take you in total:

  • Feeding your rabbit - 12 min;
  • Cooking dinner - 1h 15 min; and
  • Calling Uncle Bob - 53 min (he does like to natter on).

To find out how long it'll be before you put your feet up, input the time values in the time calculator. You don't need to change the unit - if you want to enter only minutes, click the blank place next to "min" and type in the number. The hours and minutes will automatically become zeros. You can find your result at the bottom of the time calculator - the tasks should take you 2 h 20 min in total.

Subtract time (time difference) calculator

To use the time difference calculator:

  1. Change the value of the first field ("I want") to "subtract time".
  2. Let's say you want to know how many hours of the day you have left after deducting time for sleep. In this case, change the unit in the first value field to "days" and enter "1".
  3. In the second value field of the time difference calculator, input the number you want to deduct - in this example, your sleeping hours, let's say 7h 23 min.
  4. The result will appear in the last field of the subtract time calculator. In our example, that would be your waking hours - 16 h 37 min.

You can also use the time calculator as a time duration calculator. If you want to find the duration between times:

  1. Convert both times to 24-hour format.
  2. Enter the later time in the first field.
  3. Enter the earlier time in the second row.
  4. The result will appear in the last field of the time calculator.

Multiply time calculator

To use the multiply time calculator:

  1. In the first field, choose the "multiply time" option.
  2. In the second field, enter the multiplicand - the time value you want to multiply.
  3. Enter the multiplier into the third row of the multiply time calculator.
  4. The result will appear in the last field. You can freely change the units anytime.


You have to paint a fence. You've already done 1/5 of the work, and it took you 23 minutes. You want to estimate how long it takes to paint the whole fence.

  1. In the second field of the multiply time calculator, enter "23 minutes".
  2. In the next field, enter "5" (1/5 took 23 min, so the whole fence (5/5) will take five times longer).
  3. You'll see the result is 1 h 55 min.

Time calculator - division

To use the divide time calculator:

  1. In the first field choose the "divide time" option.
  2. In the second field, enter the numerator - the time value you want to divide.
  3. Enter the denominator (the number by which you divide) into the third row of the time division calculator.
  4. The result will appear in the last field. You can change the units in the time division calculator.


You're soon starting a two-week holiday, and you decided to spend 1/3 of this time (including sleeping hours) on the beach with your other half. To count it:

  1. Change the unit in the second field to "weeks". Enter "2".
  2. To find how much is 1/3 of the time, you need to divide by 3. Enter this number into the second field of the divide time calculator.
  3. The result at the bottom says you'll spend 112 h by the sea with your beloved. You can change the unit to see this equals 4 days and 16 hours. Enough to top up that tan!

Date time calculator - calculate the time between dates

To use the date time calculator:

  1. Choose "find time between dates" in the first field.
  2. Enter an earlier date in the second field - you can either choose it from the calendar or type it in e.g. "Sep 22, 2020".
  3. Set a later date in the third field.
  4. Below you'll see the time between dates. You can change its unit in the last field of the date time calculator.


You have an exam on 18.10.2020 and want to know how many days you've got left to prepare. Today is 22.09.2020.

  1. Choose today's date in the "start date" field or type in "Sep 22, 2020" and click "Enter".
  2. Choose 18.10.2020 or type in "Oct 18, 2020" into the third field of the date time calculator.
  3. You'll see you have 26 days left.
The Fresh Start Effect: we're more likely to tackle good, important things at the start of... the day, week, month, year, ...
Credit: Jono Hey - sketchplanations.com

Time and date calculator (time to time calculator)

This option is similar to the time between dates calculator, but it's more precise and takes time (hours) into account.

Let's say you want to use the time and date calculator to know your exact age. In this case:

  1. Enter the day and time you were born.
  2. Choose today's time and date.
  3. Read your age from the last field of the date and time calculator.

This time to time calculator has an accuracy of half an hour (you can only choose 11:30, you cannot choose 11:27). If you need more precision, use the elapsed time calculator.

You could also use this time calculator - just enter a later hour in 24-hour format in the first field and an earlier hour in the second field.

How to add time manually?

Calculating time may be complicated because of the hexadecimal system. What does it mean? To put it simply, it means 60 "smaller units" make up 1 "bigger unit", e.g. 60 seconds equal 1 minute and 60 minutes equal 1 hour. We're more used to the decimal system where 1 "bigger unit" is comprised of 10 (or 100, 1000, etc.) "smaller units", e.g. 10 grams are 1 dekagram.

Keeping that in mind, let's go through some examples:

Time addition

Example: 1 h 53 min + 2 h 8 min 22 s + 46 s

  1. Add minutes to minutes, hours to hours, and seconds to seconds:

    hours = 1 h + 2 h = 3 h

    minutes = 53 min + 8 min = 61 min

    seconds = 22 s + 46 s = 68 s

  2. Convert, where possible:

    minutes = 61 min = 1 h 1 min

    seconds = 68 s = 1 min 8 s

  3. Substitute the converted values from step 2 into the formula:

    hours + minutes + seconds =

    3 h + 1 h 1 min + 1 min 8 s

  4. Add hours, minutes and seconds separately:

    hours = 3 h + 1 h = 4 h

    minutes = 1 min + 1 min = 2 min

    seconds = 8 s

  5. When there's nothing left to add, we write down the result:

    4 h + 2 min + 2 s = 4 h 2 min 8 s

  6. If there is a need to convert values, repeat the procedure from step 2.

How to subtract time without the time difference calculator?

Example: 1 day - 11 min 55 s

First method:

  1. Convert time values to the smallest unit occurring in them:

    1 day = 86400 s

    11 min 55 s = 715 s

  2. Subtract the converted values:

    86400 s - 715 s = 85685 s

  3. Convert the result to the desired unit:

    85685 s = 23 h 48 min 5 s

Second method:

This is similar to the way you would do long division.

  1. Break the bigger number into a sum of parts from which you can easily subtract:

    1 day = 24 h = 23 h + 1 h

    1 h = 60 min = 59 min + 1 min

    1 min = 60 s

    We get:

    1 day = 23 h + 59 min + 60 s

  2. Subtract from the expression you got in the first step (minutes from minutes, seconds from seconds, etc):

    23 h + 59 min + 60 s - 11 min - 55 s =

    23 h + (59 min - 11 min) + (60 s - 55 s) =

    23 h 48 min 5 s

How to calculate time? - multiplication

Example: 3 h 43 min 11 s * 6

  1. Multiply each unit separately:

    hours = 3 h * 6 = 18 h

    minutes = 43 min * 6 = 258 min

    seconds = 11 s * 6 = 66 s

  2. Convert each unit if possible:

    hours = 18 h (nothing to change here)

    minutes = 258 min = 4 h 18 min

    seconds = 66 s = 1 min 6 s

  3. Add the converted units:

    hours + minutes + seconds =

    18 h + 4 h 18 min + 1 min 6 s

    Again, hours to hours, minutes to minutes, and so on:

    (18 h + 4 h) + (18 min + 1 min) + 6 s =

    22 h 19 min 6 s

  4. Convert your time again if there is a need (step 2).

How to calculate time? - division

Example: 3 weeks / 5

  1. Convert the numerator to a smaller unit until you get a number which can be divided by 5:

    3 weeks = 3 * 7 days =

    21 days = 21 * 24 h =

    504 h = 504 * 60 min = 30,240 min

  2. Do the division:

    30,240 min / 5 = 6048 min

  3. Convert to the desired unit:

    6048 min = 100 h 48 min = 4 days 4 h 48 min

If you need some instruction on how to calculate the time between dates without the time difference calculator, check the example in the date calculator.

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