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.
How to copy an example
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Selecting an example from Help
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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) 
