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# A to Z of Excel Functions: The FLOOR.MATH Function

5 August 2019

Welcome back to our regular A to Z of Excel Functions blog. Today we look at the FLOOR.MATH function.

Not to be confused with a floor mat... This function actually rounds a number down to the nearest integer or to the nearest multiple of significance (see below). The FLOOR.MATH function employs the following syntax to operate:

FLOOR.MATH(number, [significance], [mode])

The FLOOR.MATH function has the following arguments:

• number: this is required.  This number is what is to be rounded (down for positive numbers)
• significance: this is optional.  This represents the multiple to which number is to be rounded
• mode: also optional.  For negative numbers, this controls whether number is rounded toward or away from zero.

It should be further noted that:

• by default, positive numbers with decimal portions are rounded down to the nearest integer, e.g. 6.3 is rounded down to 6, using the default significance (1)
• by default, negative numbers with decimal portions are rounded away from 0 to the nearest integer, e.g. -6.7 is rounded to -7
• by using 0 or a negative number as the mode argument, you can change the direction of the rounding for negative numbers.  For example, rounding the number -6.3 with a significance of 1 and a mode of -1 rounds toward zero (0), to -6
• the significance argument rounds the number down to the nearest integer that is a multiple of the significance specified.  The exception is where the number to be rounded is an integer.  For example, for a significance of 3, the number is rounded down to the last integer that is a multiple of 3
• if number divided by a significance of 2 or greater results in a remainder, the result is rounded down. 