The Excel ATANH Function

Inverse Hyperbolic Tangent

The atanh function returns the inverse hyperbolic tangent. Therefore,

ATANH( TANH( z ) ) = z

The equation used to calculate the inverse hyperbolic tangent is:

Inverse Hyperbolic Tangent Equation
Further information on the inverse hyperbolic functions can be found on Wikipedia

Function Description

The Excel Atanh function calculates the inverse hyperbolic tangent of a supplied number.

The syntax of the function is:

ATANH( number )

Where the number argument is a real number, between (but not equal to) -1 and 1, that you want to calculate the inverse hyperbolic tangent of.


Excel Atanh Function Examples

Column B of the following spreadsheet shows the Excel Atanh Function, used to calculate the inverse hyperbolic tangent of three different values:

 Formulas:
  A B
1 number ATANH
2 -0.8 =ATANH( A2 )
3 0 =ATANH( A3 )
4 0.5 =ATANH( A4 )
 Results:
  A B
1 number ATANH
2 -0.8 -1.098612289
3 0 0
4 0.5 0.549306144

For further details and examples of the Excel Atanh function, see the Microsoft Office website.


Atanh Function Errors

If you get an error from the Excel Atanh Function, this is likely to be one of the following:

Common Errors
#NUM! - Occurs if the supplied number is ≤ -1 or ≥ 1.
#VALUE! - Occurs if the supplied number argument is not recognized as a numeric value.