Decimal Hours vs. Hours:Minutes (hh:mm)
We talk with customers every day who are confused about decimal hours (i.e., 4.25) and hours:minutes (i.e., 4:15). Here, we go into the math on performing the decimal to hours:minutes conversion and the reasons why and when you may need to convert time in this manner.
It's kind of a big deal if your payroll utilizes employee hours!
Spoiler
There is an awesome hours converter link located at the bottom of this page, or, to make it easy, just click here.
The big thing to look for is a decimal point (.) or colon (:)
Decimal hours can sometimes cause a bit of confusion for people who are used to looking at hours in the hh:mm format. Here are a few examples of decimal hours and how to interpret them…
- 8.00 hours - this is exactly 8 hours or 8:00 in the hh:mm format - note the use of a colon, not a decimal point.
- 8.25 hours - this is 8 and 1/4 hours, 8 hours and 15 minutes, or 8:15 (hh:mm), again, note the colon.
- 8.50 hours - here we have 8 and ½ hours, 8 hours and 30 minutes, or 8:30.
- 8.75 hours - 8 hours and 45 minutes or 8:45.
Here are a few examples that are commonly confused
- 8.20 hours - you may want to read this as 8 hours and 20 minutes, but it is actually 8 hours and 12 minutes (notice the decimal point).
- 8.45 hours - this one is 8 hours and 27 minutes.
Why Use Decimal Hours? We Use Decimal Hours for Two Reasons…
They are more precise - decimal hours are almost two times more precise than minute hours. Minute hours have a maximum of 1/60 resolution, while decimal hours have a 1/100 resolution. Decimal hours are easier to work with. Imagine trying to multiply 8:12 (which is 8 hours and 12 minutes) by an employee hourly rate. It’s much easier to multiply 8.20 (or 8 hours and 12 minutes) by an hourly rate to calculate payroll.
A Bit of Time Clock History
While we could not find a lot of data on why the hh:mm format has emerged as the preferred timekeeping method, we do have a few ideas.
- The very first time clocks were people. A person would simply write down when an employee got to work and when they left. What would they write down? Times such as 8:00 a.m. and 5:00 p.m. To calculate worked time, the person responsible for payroll would figure hours and minutes worked but would then convert to decimal hours to do the multiplication.
- The next time clocks were old-school, wall-mounted punch clocks. An employee would insert his or her punch card and time would be punched in the hh:mm format. Then, again, a payroll person would convert the hh:mm times to decimal hours.
- Computer-based punching came next. The early computer systems simply mimicked their predecessors. The hh:mm addition persisted, and, through the program, the hh:mm format would be converted to decimal hours for payroll purposes.
So, Why the Big Ole Hairy Article?
We wanted to tell you that we built a nice converter for you, here it is...
Minutes To Hours Calculator
