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Excel

ACOS function in Excel

Returns the arccosine of a number

=ACOS(number)

ACOS syntax and parameters

One argument, one required.

  • numbernumberRequired

    The cosine of the angle you want and must be from -1 to 1.

ACOS examples

Formulas you'll actually reuse.

  1. The arccosine of 0.5, in radians:

    =ACOS(0.5)

    Result1.0472

  2. The same angle in degrees — wrap in DEGREES:

    =DEGREES(ACOS(0.5))

    Result60

ACOS in Google Sheets

Same name — your formula ports as-is.

Try ACOS in the playground

Edit the example — nothing to install.

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

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Related functions

More ways Excel gets this done.