The Excel CSC Function


The Cosecant is the reciprocal of the Sine.

Therefore, for the simple right-angled triangle below, the cosecant of the angle θ is equal to the hypotenuse, h, divided by the opposite side, o.

Right-Angled Triangle

I.e. for the triangle above,

Cosecant Equation
The trig. ratios are discussed further on the Wikipedia Trigonometric Ratios Page

Function Description

The Excel Csc function calculates the cosecant of a given angle.

Note: the Csc function was only introduced in Excel 2013 and so is not available in earlier versions of Excel.

The syntax of the function is:

CSC( number )

Where the number argument is the angle (in radians) that you want to calculate the cosecant of. This must be between -2^27 and +2^27.

If the supplied number argument is equal to 0, the Csc function returns the #DIV/0! error.

Converting from Degrees to Radians

If your angle is in degrees, you will need to convert it into radians before supplying it to the Csc function. This can be done using the Excel Radians function:

=RADIANS( degrees )
An example of this is given below.

Excel CSC Function Examples

The following spreadsheet shows the Excel Csc Function, used to calculate the Cosecant of four different angles:

1 =CSC( -6 )
2 =CSC( 1.5707963267949 )
3 =CSC( PI() / 4 )
4 =CSC( RADIANS( 45 ) )
1 3.578899547
2 1
3 1.414213562
4 1.414213562

Note that, in the above spreadsheet:

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

Csc Function Errors

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

Common Errors
#DIV/0! - Occurs if the supplied number is equal to zero.
#NUM! - Occurs if the supplied number is less than -2^27 or is greater than 2^27.
#VALUE! - Occurs if the supplied number is not recognised as a numeric value.