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Excel

COS function in Excel

Returns the cosine of a number

=COS(number)

COS syntax and parameters

One argument, one required.

  • numbernumberRequired

    The angle in radians for which you want the cosine.

COS examples

Formulas you'll actually reuse.

  1. Cosine of 60° — convert degrees first, trig functions take radians:

    =COS(RADIANS(60))

    Result0.5

  2. Cosine of PI() radians:

    =COS(PI())

    Result-1

COS in Google Sheets

Same name — your formula ports as-is.

Try COS in the playground

Edit the example — nothing to install.

Preloaded with the COS formula from Example 1 — change anything and watch it respond.

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Related functions

More ways Excel gets this done.