Tom’s Tutorials For Excel: Rounding Elapsed Time by the Half-Hour

Tom’s Tutorials For Excel: Rounding Elapsed Time by the Half-Hour

Here are 3 formulas that round an elapsed time by the half-hour, in terms of nearest half-hour, up to the next half-hour, and down to the last (lower) half-hour.

In the picture, notice the differences for each employee’s elapsed time in decimalized half-hour segments, depending on if, and how, you decide to round or not round. The number 48 in the formulas relates to the count of half-hour (30-minute) segements that comprise a full calendar day.


The formula that subtracts the raw difference, entered in cell D3 and copied down:
=(C3-B3)*48

The subtraction formula that rounds to the nearest half-hour, entered in cell E3 and copied down:
=ROUND((C3-B3)*48,0)

The subtraction formula that rounds up to the next half-hour, entered in cell F3 and copied down:
=CEILING((C3-B3)/(1/48),1)

The subtraction formula rounding down to the prior half-hour, entered in cell G3 and copied down:
=FLOOR((C3-B3)/(1/48),1)