How to use the Excel LN function

Summary

The Excel LN function returns the natural logarithm of a given number.

Purpose

Get the natural logarithm of a number

Return value

The natural logarithm

Syntax

=LN (number)

Arguments

number - A number to take the natural logarithm of.

Usage notes

The natural logarithm function is the equivalent to log base e of a number. Where e is Euler's number.

= LN( number) = LOG( number, e) // Where e ≈ 2.7128 or EXP(1)

Graph

x	ln( x)
0.5	-0.69
1	0.00
1.5	0.41
2	0.69
2.5	0.92
3	1.10
3.5	1.25
4	1.39
4.5	1.50
5	1.61

The natural logarithm function is also the inverse of the exponential function.

= number = LN( EXP(number))

Related functions

Excel LOG Function

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

Good links

Microsoft LN function documentation

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