Decimal Hours to HH:MM:SS Time Calculator

Convert the number of hours as a decimal value into the time expressed in HH:MM:SS.


Learn how we calculated this below

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How to Convert Decimal Hours to Time in HH:MM:SS

If you have the number of hours as a decimal value, you might want to express it in hours, minutes, and seconds. There are a few steps to follow in order to do this conversion.

Icon showing a clock to convey time

First, find the number of whole hours in the decimal string. Do this by taking the whole number to the left of the decimal point; this gives you the hours value.

The second step is to find the number of remaining minutes. To find the minutes, multiply the decimal value, which is the number to the right of the decimal, by 60. The whole number to the left of the decimal point in the resulting number is the number of minutes.

The number of seconds is the remaining decimal number multiplied by 60.

The final step is to rewrite the number in the form HH:MM:SS, where HH is the hours, MM is the minutes, and SS is the seconds.

You can also use our time calculator for this conversion.

Once you have the time in HH:MM:SS format, you can use it with our hours calculator to find how much time elapsed.

For example, let’s convert 12.675 hours to hours, minutes, and seconds.

Start by finding the number of hours.

12.675 hours = 12 hours + .675 hours
full hours = 12

Then, find the number of minutes

minutes = .675 hours × 60 minutes
minutes = 40.5 minutes
full minutes = 40

Find the remaining seconds

seconds = .5 minutes × 60 seconds
seconds = 30 seconds

Finally, rewrite as HH:MM:SS

time = 12:40:30

Try our time to hours calculator to learn how to convert the time back to a decimal.