# Excel LOG Function

Summary

The Excel LOG function returns the logarithm of a given number, using a supplied base. The base argument defaults to 10 if not supplied.

Purpose

Get the logarithm of a number

Return value

The logarithm

Syntax

=LOG (number, [base])

Arguments

**number**- Number for which you want the logarithm.**base**- [optional] Base of the logarithm. Defaults to 10.

Usage notes

The LOG function allows you to get the logarithm of a number with a specified base.

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