FLOOR.MATH Function
Rounds down to a multiple of significance, with a mode for negative numbers.
Syntax
Parameters
| Parameter | Description | Required |
|---|---|---|
| number | The value you want to round. | Required |
| significance | The multiple to round to. Defaults to 1 if omitted. | Optional |
| mode | Controls rounding of negative numbers. 0 (default) rounds toward zero; any other value rounds away from zero (more negative). | Optional |
Basic Example
Round down to the nearest integer
=FLOOR.MATH(24.3)With default significance 1 and mode 0, 24.3 rounds down to 24.
Advanced Examples
Example 1: Negative numbers: toward zero vs away from zero
Controlling how -5.5 is rounded.Mode 0 rounds toward zero; a non-zero mode rounds away from zero.
=FLOOR.MATH(-5.5, 1, 0)Example 2: Round to a chosen decimal multiple
Round 6.05 down to the nearest 0.1.Pass significance 0.1.
=FLOOR.MATH(6.05, 0.1)How FLOOR.MATH Works
FLOOR.MATH rounds number down to the nearest multiple of significance (default 1). Unlike classic FLOOR, it permits any sign combination. The mode argument only affects negative numbers: mode 0 rounds toward zero, and any other value rounds away from zero.
Important Notes & Limitations
Only available in Excel 2013 and later (and Microsoft 365); older versions return #NAME?.
For positive numbers, mode has no effect; it always rounds down.
Workbooks saved for pre-2013 compatibility will not support this function.
Common Errors & Fixes
#NAME?Used in an Excel version earlier than 2013.Fix: Use FLOOR, or open the file in Excel 2013+ / Microsoft 365.
#VALUE!A non-numeric argument was supplied.Fix: Use numeric values or numeric references.
Download Practice File
FLOOR.MATH
floor-mathPractice FLOOR.MATH with Real Data
Download a sample CSV file with pre-populated data and practice exercises for the FLOOR.MATH function. Works in both Excel and Google Sheets.
File format: CSV (comma-separated values) - opens in Excel, Google Sheets, and all spreadsheet apps