Inverse Tangent (Arctan) Calculator
Inverse Tangent (Arctan) Calculator
Arctan reverses the tangent function — instead of finding the tangent of a known angle, it finds the angle whose tangent equals a value you already have, and is also written tan⁻¹. Enter any real number, and this calculator finds the corresponding angle in both degrees and radians. Because tangent itself is unbounded, arctan accepts any real number as input, unlike arcsin and arccos, which only accept values between −1 and 1.
- Arctan (written tan⁻¹ or atan) is the inverse of the tangent function, answering "what angle has this tangent value?" rather than "what is the tangent of this angle?"
- Unlike arcsin and arccos, arctan accepts any real number as input, since tangent itself is unbounded and can produce any value.
- Arctan returns a single angle between −90° and 90° (exclusive), called the principal value, and never returns exactly ±90° since tangent is undefined there.
What does arctan actually calculate?
It finds the angle (within −90° to 90°) whose tangent equals the value you provide — the reverse operation of the tangent function.
What is arctan(1)?
45°, since tan(45°) = 1.
Inverse Tangent (Arctan) Calculator
Arctan reverses the tangent function — instead of finding the tangent of a known angle, it finds the angle whose tangent equals a value you already have, and is also written tan⁻¹. Enter any real number, and this calculator finds the corresponding angle in both degrees and radians. Because tangent itself is unbounded, arctan accepts any real number as input, unlike arcsin and arccos, which only accept values between −1 and 1.
- Arctan (written tan⁻¹ or atan) is the inverse of the tangent function, answering "what angle has this tangent value?" rather than "what is the tangent of this angle?"
- Unlike arcsin and arccos, arctan accepts any real number as input, since tangent itself is unbounded and can produce any value.
- Arctan returns a single angle between −90° and 90° (exclusive), called the principal value, and never returns exactly ±90° since tangent is undefined there.
What does arctan actually calculate?
It finds the angle (within −90° to 90°) whose tangent equals the value you provide — the reverse operation of the tangent function.
What is arctan(1)?
45°, since tan(45°) = 1.