The Excel PI Function

The Excel PI function returns the value of the mathematical constant π (pi), accurate to 15 digits (14 decimal places).

I.e. the function returns the value 3.14159265358979

The Pi function takes no arguments and therefore has the syntax:

PI( )

Pi Function Examples

The spreadsheet below shows three examples of the Excel Pi function.

 Formulas:
  A B
1 =PI( )  
2 =SIN( PI( ) / 2 )  
3 =2 * PI( ) * 5 - circumference of a circle with radius 5
 Results:
  A
1 3.141592654
2 1
3 31.41592654

Further examples of the Excel Pi function are provided on the Microsoft Office website.