The Excel FLOOR function rounds a number down to the nearest multiple of a significance you choose — the mirror image of CEILING.
Syntax
| Argument | Description | |
|---|---|---|
number | Required | The value you want to round down. |
significance | Required | The multiple to round down to. For positive numbers it must be positive; mixing signs causes an error. |
How to use it
FLOOR rounds down (toward zero for positives) to the nearest multiple of significance:
FLOOR is the counterpart to CEILING: CEILING rounds up to the next multiple, FLOOR rounds down to the previous one. The newer FLOOR.MATH makes significance optional and handles negatives with a mode argument.
Opposite signs error. If number is positive and significance is negative (or vice-versa), classic FLOOR returns an error. Match the signs, or switch to FLOOR.MATH.
Try it: interactive demo
Pick a FLOOR example to see the formula and its result.
Practice workbook
Frequently asked questions
How is FLOOR different from ROUNDDOWN?
Why does FLOOR return an error?
number and significance have opposite signs. Match them, or use FLOOR.MATH, which has no such restriction.Is FLOOR the opposite of CEILING?
=FLOOR(23, 5) is 20; =CEILING(23, 5) is 25.Should I use FLOOR or FLOOR.MATH?
significance optional (defaults to 1) and adds a mode argument for negatives. Use it for new work unless you need backward compatibility.Master functions like this in one day
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