# Inverse Tangent Calculator – Calculate arctan(x)

Find the angle in degrees or radians using the inverse tangent with the arctan calculator below.

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## How to Find Arctan

Arctan is a trigonometric function to calculate the inverse tangent. Arctan can also be expressed as tan^{-1}(x).

Arctan is used to undo or reverse the tangent function. If you know the tangent of an angle, you can use arctan to calculate the angle.

To calculate arctan, use a scientific calculator and the *atan* function, or just use the calculator above. Most scientific calculators require the angle value in radians to solve for tan.

### Inverse Tangent Formula

The inverse tangent formula is:

y = tan(x) | x = arctan(y)

Thus, if *y* is equal to the tangent of *x*, then *x* is equal to the arctan of *y*.

## Inverse Tangent Graph

If you graph the arctan function for every possible value of tangent, it forms a curve from (-∞, –π / 2) to (∞, π / 2).

## Inverse Tangent Table

The table below shows common tangent values and the arctan, or angle for each of them.

Tangent | Angle (degrees) | Angle (radians) |
---|---|---|

-∞ | -90° | –π / 2 |

-√3 | -60° | –π / 3 |

-1 | -45° | –π / 4 |

–√3 / 3 | -30° | –π / 6 |

0 | 0° | 0 |

√3 / 3 | 30° | π / 6 |

1 | 45° | π / 4 |

√3 | 60° | π / 3 |

∞ | 90° | π / 2 |

You might also be interested in our inverse sine and inverse cosine calculators.