The **LOG10** Excel function is a *Math* formula that returns the logarithm of a given number, using base 10. The logarithm of a given number is the exponent to which another fixed number (the *base* 10) must be raised to produce that number. In this guide, we’re going to show you how to use the **LOG10 **function in Excel and also go over some tips and error handling methods.

## Supported versions

- All Excel versions

## LOG10 Excel Function Syntax

LOG10(number)

## Arguments

number |
A positive real number for which you want the logarithm. |

## Example

Use the **LOG10** Excel function to calculate the logarithm of argument **number** to the base *10***.** The equivalent math formula would be *log _{10}number*. Based on this, we can say that

*=LOG10(number, 10)*is equal

*LOG10(number)*. Here is a sample use:

=LOG10(100) returns the logarithm of

*100*,*2*## Tips

- The base is always 10 and the equivalent math formula is =log
_{10}number - Alternatively, you can use
**LOG**function without the**[base]**argument to use base 10. - Use the
**LN**function to calculate the natural logarithm of a given number.

## Issues

- The
**number**argument value must be a positive real number. Otherwise, the**LOG10**Excel function will return a*#NUM!*error.