Current decimal time

Regular time
Decimal time
Decimal hours

Decimal time

Decimal time is a way of time keeping that aligns with our decimal system (based on factors of 10). Especially converting between time notation hh:mm:ss and decimal notation hh.mmss works very well.

Decimal time is built like this:

A day has 10*100*100 = 100'000 seconds. This comes close to the current day length of 86400 seconds while being decimal.
This causes a decimal second to be 15% faster than a regular second.
The french used this system for a short while.


Layout of a day written as decimal time: D.HMMSS...

This layout is very easy to read and calculate with by merely shifting the decimal point:

All times above are the same decimal time




Metric time vs. Decimal time

Metric time defines a second, and then time-keeping is done using seconds only. SI prefixes are applied for large or small numbers.

Metric time does not cares for the actual time an entire day takes, and it doesn't changes the current definition of a second. The system is mostly suitable to measure time intervals but not for daily time keeping tasks

Decimal time adjusts the length of a second to allow it to be used for the daily time-keeping tasks.


Enter "classic" time or decimal time, then press the appropriate button. Please allow for up to 1 second of rounding error. The converter accepts values that are too large. If you want to know how much decimal time is 1000 classic seconds, you can just fill in 1000 into the box for the seconds. You don't need to convert to minutes and seconds manually.

Created in 2016 by somebody who is really upset with how we keep time. More stuff