LN
Math & Trig
Returns the natural logarithm (base e) of a number.
Translations
EnglishLN
FrenchLN
SpanishLN
GermanLN
ItalianLN
PortugueseLN
DutchLN
PolishLN
RussianLN
TurkishLN
CzechLN
HungarianLN
SwedishLN
DanishLN
FinnishLUONNLOG
Syntax
LN(number)Arguments
numberPositive number
Examples
=LN(1)0
LN of 1 is always 0
=LN(EXP(1))1
LN and EXP are inverses
=LN(2.718)~1
LN of e is 1
Tips & Best Practices
- •e is approximately 2.71828
- •Use EXP to reverse LN
- •Common in growth calculations
Common Mistakes
- •Applying LN to zero or a negative number, which returns a #NUM! error since the natural logarithm is only defined for positive numbers
- •Confusing LN with LOG10 or a base-10 LOG - LN specifically uses the mathematical constant e as its base, not 10
- •Forgetting that LN and EXP are inverse operations, leading to redundant nested formulas like LN(EXP(x)) when x alone would suffice
Related Functions
Frequently Asked Questions
Why does LN return #NUM!?
The input is zero or negative - the natural logarithm is only defined for positive real numbers.
What's the difference between LN and LOG?
LN always uses base e, the mathematical constant approximately equal to 2.71828. LOG lets you specify any base, defaulting to 10 if you don't.
How do I reverse a natural logarithm calculation?
Use EXP - if LN(x) gives you a result, EXP of that result returns you to x, since they're inverse operations.
Need to translate a formula using LN?
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