Time Calculator | Add, Subtract, Multiply, Divide Time
Calculator Use
Time calculator to add, subtract, multiply and divide time in days, hours, minutes and seconds.
Use this time calculator to:
- Add Time
- Subtract Time
- Multiply Time by a Number
- Divide Time by a Number
- Divide Time by Time
The calculator can add and subtract time segments or multiply and divide time by a number or decimal. Answers include equivalent time in total days, hours, minutes or seconds. Also divide a time by a time and the answer includes the quotient as an integer with the remainder in time units.
How to Calculate Time
How to do math operations with time is explained below. See examples of adding, subtracting, multiplying and dividing segments of time.
How to Add Time
Add days, hours, minutes and seconds working from smallest unit of time to largest.
- Add the seconds
- If total seconds is greater than 59, subtract 60 from seconds and carry 1 to minutes
- Add the minutes including any carried over from calculating seconds
- If total minutes is greater than 59, subtract 60 from minutes and carry 1 to hours
- Add the hours including any carried over from calculating minutes
- If total hours is greater than 24, subtract 24 from hours and carry 1 to days
- Add the days including any carried over from calculating hours
Adding Time Example Problem
Add 2 days 21 hours 45 minutes 39 seconds to 5 days 10 hours 45 minutes 22 seconds
- 39 seconds + 22 seconds = 61 seconds
- 61 seconds - 60 = 1 second, carry 1 to minutes
- 1 minute + 45 minutes + 45 minutes = 91 minutes
- 91 minutes - 60 = 31 minutes, carry 1 to hours
- 1 hour + 21 hours + 10 hours = 32 hours
- 32 hours - 24 = 8 hours, carry 1 to days
- 1 day + 2 days + 5 days = 8 days
- Completed Adding Time Math Problem
How to Subtract Time
Subtract days, hours, minutes and seconds working from smallest unit of time to largest.
- Subtract the seconds
- If the seconds you are subtracting is greater than the top number, borrow 1 minute from the top minutes and add 60 to the top seconds. Then subtract.
- Subtract the minutes
- If the minutes you are subtracting is greater than the top number, borrow 1 hour from the top hours and add 60 to the top minutes. Then subtract.
- Subtract the hours
- If the hours you are subtracting is greater than the top number, borrow 1 day from the top days and add 24 to the top hours. Then subtract.
- Subtract the days
Note that in any case where you need to borrow, if the next highest unit is 0 then borrow from the 2nd highest unit. Just as you would in long subtraction, borrow from the next highest place value.
Subtracting Time Example Problem
Subtract 2 days 21 hours 56 minutes 18 seconds from 5 days 0 hours 10 minutes 13 seconds
- Subtract seconds
- 13 seconds is less than 18 seconds so borrow 1 from the top minutes
- 1 minute = 60 seconds so add 60 seconds to 13 to get 73
- 73 seconds - 18 seconds = 55 seconds
- Subtract minutes
- 9 minutes is less than 56 minutes so borrow 1 from hours
- There are 0 hours so borrow 1 from days
- 1 day = 24 hours and 1 hour = 60 minutes, so add 24 to hours, then borrow 1 from hours to leave 23
- Add 60 minutes to 9 to get 69
- 69 minutes - 56 minutes = 13 minutes
- Subtract hours
- 23 hours - 21 hours = 2 hours
- Subtract days
- 4 days - 2 days = 2 days
- Completed Subtracting Time Math Problem
How to Multiply Time
Multiply days, hours, minutes and seconds by a multiple, working from smallest unit of time to largest.
- Multiply each unit of time by the multiple
- Working from smallest unit of time to largest, convert excess time units to next higher unit
- If seconds are greater than 59, divide by 60 to get a whole number and remainder
- Keep the remainder as total seconds and add the whole number to minutes
- If minutes are greater than 59, divide by 60 to get a whole number and remainder
- Keep the remainder as total minutes and add the whole number to hours
- If hours are greater than 23, divide by 24 to get a whole number and remainder
- Keep the remainder as total hours and add the whole number to days
Multiplying Time Example Problem
Multiply 2 days 10 hours 32 minutes 16 seconds by 5
- Multiply each unit of time by 5
- 80 seconds is greater than 59 so convert excess to minutes
- 80 divided by 60 equals 1 with a remainder of 20
- Keep 20 seconds and carry the 1 to minutes
- 160 + 1 = 161 minutes
- 161 minutes is greater than 59 so convert excess to hours
- 161 divided by 60 equals 2 with a remainder of 41
- Keep 41 seconds and carry the 2 to hours
- 50 + 2 = 52 hours
- 52 hours is greater than 24 so convert excess to days
- 52 divided by 24 equals 2 with a remainder of 4
- Keep 4 hours and carry the 2 to days
- 10 + 2 = 12 days
- Completed Multiplying Time Math Problem
How to Divide Time
Divide days, hours, minutes and seconds by a divisor, working from smallest unit of time to largest.
- Divide each unit of time by the divisor
- Then, working from largest to smallest unit of time, convert any decimal values to whole numbers shifting the decimal amount to a smaller time unit
- If days has a decimal, keep the whole number as total days and convert the decimal to hours
- Since 1 day = 24 hours, multiply the decimal by 24 and add the result to hours
- If hours has a decimal, keep the whole number as total hours and convert the decimal to minutes
- Since 1 hour = 60 minutes, multiply the decimal by 60 and add the result to minutes
- If minutes has a decimal, keep the whole number as total minutes and convert the decimal to seconds
- Since 1 minute = 60 seconds, multiply the decimal by 60 and add the result to seconds
- If seconds has a decimal, you can usually leave this as your final answer depending on your application
Dividing Time Example Problem
Divide 4 days 10 hours 13 minutes 16 seconds by 4
- Divide each unit of time by 4
- Work from smallest unit of time to leargest convert any decimal values to whole numbers
- Hours is not a whole number so convert the decimal to minutes
- 2.5 hours is 2 hours plus 0.5 hours
- Since 1 hour = 60 minutes, 0.5 of 1 hour equals 0.5 of 60 minutes = 30 minutes
- Keep the 2 hours and carry 30 to minutes
- 30 + 3.25 = 33.25 minutes
- Minutes is not a whole number so convert the decimal to seconds
- 33.25 minutes is 33 minutes plus 0.25 minutes
- Since 1 minute = 60 seconds, 0.25 of 1 minute equals 0.25 of 60 seconds = 15 seconds
- Keep the 33 minutes and carry 15 to seconds
- 15 + 4 = 19 seconds
- Completed Dividing Time Math Problem