Decimal Hours Converter

Convert a known duration to decimal hours, or turn decimal hours into hours and minutes. Add seconds only when you need them.

Known duration

Conversion direction

Changing direction clears all entered values. Your options stay selected.

Hours

Minutes

Use whole, nonnegative numbers. Once one part is filled, blank parts mean zero. Minutes and seconds may exceed 59.

More options

Use seconds

Decimal places

Result

Enter a known duration to see the conversion.

h = hours; min = minutes; s = seconds. Hours are accumulated durations.

Calculation details

This converts a known duration. It does not calculate paid time or apply payroll rounding.

Need a duration from two clock times? Use Time Duration Calculator.

How to convert hours and minutes

Choose the direction. Enter whole hours and minutes, or one decimal-hour value. Once one duration part is filled, blank parts count as zero.
Open More options to use seconds. Forward conversion offers 2 or 4 decimal places. Minutes and seconds may exceed 59; the parts are combined into one duration.
Read the result and its rounding note before copying. Changing direction clears the values instead of reusing a rounded answer.

Decimal hours are not hours and minutes

An ordinary hour contains 60 minutes or 3,600 seconds. Decimal hours = hours + minutes ÷ 60 + seconds ÷ 3,600. The decimal is a fraction of a conventional hour, not a base-100 clock.

7 hours 30 minutes is 7.50 hours, not 7.30 hours. Conversely, 7.30 decimal hours is 7 hours 18 minutes. The digits after the decimal point are not a minute count.

For reverse conversion, multiply decimal hours by 60 for total minutes or by 3,600 for total seconds. Round the total once, halfway up, then split it into parts. Hours never reset at midnight.

About marks numerical rounding. A positive value that would round to zero is shown as Less than the smallest display step. Changing precision always uses the original input.

Worked conversion examples

7 hours 30 minutes gives 7 + 30 ÷ 60 = 7.50 decimal hours. 2 hours plus 90 minutes gives 3.50 hours after combining the parts.

One minute is about 0.02 hours at 2 decimal places or about 0.0167 hours at 4 places. Two decimal places do not preserve every second.

7.30 hours gives 7 hours 18 minutes. 7.58 hours gives about 7 hours 35 minutes, or exactly 7 hours 34 minutes 48 seconds when seconds are enabled.

40 hours 15 minutes gives 40.25 hours. Reverse conversion keeps the full 40 hours 15 minutes: this is a duration, not a time of day.

Conversion, not a timesheet policy

This page converts a known duration. It does not subtract clock times, deduct breaks, calculate pay or apply an employer’s quarter-hour or tenth-hour rounding policy.

The maximum duration is 1,000,000 hours. Duration parts must be whole numbers; decimal hours accept up to 6 decimal places. Dates, time zones, daylight saving and historical decimal clocks are outside this conversion.

Your entries

The arithmetic runs in your browser. This tool adds no input upload, saved record or input-bearing URL. Existing website consent, analytics and network services remain separate.

Decimal-hour questions

Not as decimal hours. 0.30 × 60 is 18 minutes, so 7.30 hours is 7 hours 18 minutes. Enter 7 hours and 30 minutes in the duration fields to get 7.50 hours.

Yes. These are accumulated durations, not clock readings. For example, 40.25 hours stays 40 hours 15 minutes rather than wrapping into one day.

Reverse conversion rounds to the nearest minute without seconds, or to the nearest second with seconds enabled. Both use the original decimal-hour input. About shows when rounding changes the value.

No. It changes how a known duration is written. It does not decide which time is paid, deduct breaks or calculate money. Use Time Duration Calculator if you first need the interval between two clock times.