Back

# Math.log10

## Math.log10

The Math.log10() function returns the base 10 logarithm of a number, that is

$∀x>0,Math.log10(x)=log10(x)=the uniqueysuch that10y=x\forall x > 0, \mathtt{\operatorname{Math.log10}(x)} = \log_10(x) = \text{the unique} \; y \; \text{such that} \; 10^y = x$

## Syntax

Math.log10(x)

### Parameters

x
A number.

## Description

If the value of x is less than 0, the return value is always NaN.

Because log10() is a static method of Math, you always use it as Math.log10(), rather than as a method of a Math object you created (Math is not a constructor).

## Examples

### Using Math.log10()

Math.log10(2);      // 0.3010299956639812
Math.log10(1);      // 0
Math.log10(0);      // -Infinity
Math.log10(-2);     // NaN
Math.log10(100000); // 5


## Polyfill

This can be emulated with the following function:

Math.log10 = Math.log10 || function(x) {
return Math.log(x) / Math.LN10;
};