What units does the calculator use?

Input is in degrees. We convert to radians internally: cos(degrees × π/180).

What is the output range?

Cosine always returns a value between -1 and 1.

Calculate cosine of an angle. Enter angle in degrees to get cos(angle).

Angle (degrees)

What units does the calculator use?: Input is in degrees. We convert to radians internally: cos(degrees × π/180).
What is the output range?: Cosine always returns a value between -1 and 1.

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Convert Celsius to Fahrenheit and Fahrenheit to Celsius instantly. Free temperature converter.

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Calculate tip and split the bill. Enter bill amount, tip percentage, and number of people.

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Convert numbers to Roman numerals and Roman numerals to numbers. Supports 1–3999.

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Calculate C(n,r) — the number of ways to choose r items from n without order. Uses n!/(r!(n-r)!).

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Calculate the number of ways to choose r items from n with repetition allowed. Formula: C(n+r-1, r).

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Count how many permutations of n objects are even (expressible as an even number of swaps). For n ≥ 2, equals n!/2.