/JavaScript

# Math.log10()

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

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

## Syntax

Math.log10(x)


### Parameters

x

A number.

### Return value

The base 10 logarithm of the given number. If the number is negative, NaN is returned.

## 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).

This function is the equivalent of Math.log(x) / Math.log(10). For log10(e) use the constant Math.LOG10E which is 1 / Math.LN10.

## 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.LOG10E;
};


## Browser compatibility

Desktop Mobile Server
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet Deno Node.js
log10
38
12
25
No
25
8
38
38
25
25
8
3.0
1.0
0.12.0