Purpose
Return value
Arguments
- number - The number to round down.
- num_digits - The place at which number should be rounded.
Syntax
Usage notes
The ROUNDDOWN function rounds numbers down. Unlike standard rounding, where only numbers less than 5 are rounded down, ROUNDDOWN rounds all numbers down. For example:
=ROUNDDOWN(3.9,0) // returns 3
ROUNDDOWN takes two arguments, number and num_digits. Number is the number to be rounded, and num_digits is the place at which number should be rounded. When num_digits is greater than zero, the ROUNDDOWN function rounds on the right side of the decimal point. When num_digits is less or equal to zero, the ROUNDDOWN function rounds on the left side of the decimal point. Use zero (0) for num_digits to round to the nearest integer. The table below summarizes this behavior:
| Digits | Behavior |
|---|---|
| >0 | Round down to nearest .1, .01, .001, etc. |
| <0 | Round down to nearest 10, 100, 1000, etc. |
| =0 | Round down to nearest 1 |
Round to right of decimal
To round down values to the right of the decimal point, use a positive number for digits:
=ROUNDDOWN(A1,1) // Round down to 1 decimal place
=ROUNDDOWN(A1,2) // Round down to 2 decimal places
=ROUNDDOWN(A1,3) // Round down to 3 decimal places
=ROUNDDOWN(A1,4) // Round down to 4 decimal places
Round to left of decimal
To round down values to the left of the decimal point, use zero or a negative number for digits:
=ROUNDDOWN(A1,0) // Round down to nearest 1
=ROUNDDOWN(A1,-1) // Round down to nearest 10
=ROUNDDOWN(A1,-2) // Round down to nearest 100
=ROUNDDOWN(A1,-3) // Round down to nearest 1000
=ROUNDDOWN(A1,-4) // Round down to nearest 10000
Nesting inside ROUNDDOWN
Other operations and functions can be nested inside ROUNDOWN. For example, to round down the result of A1 divided by B1, you can use a formula like this:
=ROUNDDOWN(A1/B1,0) // round down result to nearest integer
Other rounding functions
Excel provides a number of of rounding functions, each with a different behavior:
- To round with standard rules, use the ROUND function.
- To round to the nearest multiple, use the MROUND function.
- To round down to the nearest specified place, use the ROUNDDOWN function.
- To round down to the nearest specified multiple, use the FLOOR function.
- To round up to the nearest specified place, use the ROUNDUP function.
- To round up to the nearest specified multiple, use the CEILING function.
- To round down and return an integer only, use the INT function.
- To truncate decimal places, use the TRUNC function.
