ACOS function

Returns the arccosine, or inverse cosine, of a number. The arccosine is the angle whose cosine is number. The returned angle is given in radians in the range 0 (zero) to pi.



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


If you want to convert the result from radians to degrees, multiply it by 180/PI() or use the DEGREES function.



Description (Result)


Arccosine of -0.5 in radians, 2*pi/3 (2.094395)


Arccosine of -0.5 in degrees (120)


Arccosine of -0.5 in degrees (120)

Need more help?

Expand your Office skills
Explore training
Get new features first
Join Office Insiders

Was this information helpful?

Thank you for your feedback!

Thank you for your feedback! It sounds like it might be helpful to connect you to one of our Office support agents.