# LN

Returns the natural logarithm of a number. Natural logarithms are based on the constant e (2.71828182845904).

Syntax

LN(number)

Number     is the positive real number for which you want the natural logarithm.

Remark

LN is the inverse of the EXP function.

Example

The example may be easier to understand if you copy it to a blank worksheet.

1. Create a blank workbook or worksheet.
2. Select the example in the Help topic.

Note   Do not select the row or column headers.

Selecting an example from Help
1. Press CTRL+C.
2. In the worksheet, select cell A1, and press CTRL+V.
3. To switch between viewing the results and viewing the formulas that return the results, press CTRL+` (grave accent), or on the Formulas tab, in the Formula Auditing group, click the Show Formulas button.
A B
Formula Description (Result)
=LN(86) Natural logarithm of 86 (4.454347)
=LN(2.7182818) Natural logarithm of the value of the constant e (1)
=LN(EXP(3)) Natural logarithm of e raised to the power of 3 (3)

Applies to:
Excel 2003