What range does asin and acos accept?

For arcsin and arccos the input must be between −1 and 1 (inclusive). Arctan accepts any number.

In what units is the result?

The angle is returned in degrees.

Enter a value (−1 to 1 for asin/acos) to get the angle in degrees: arcsin, arccos, arctan.

Value (e.g. 0.5 for sin/cos; any for tan)

What range does asin and acos accept?: For arcsin and arccos the input must be between −1 and 1 (inclusive). Arctan accepts any number.
In what units is the result?: The angle is returned in degrees.

Celsius to Fahrenheit Converter

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

Tip Calculator

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

Roman Numeral Converter

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

Combinations Calculator

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

Combinations with Replacement Calculator

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

Even Permutations Calculator

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