Below is an *inverse tangent calculator* (or *arctan calculator*), which calculates an angle from the ratio from the tangent function. Enter a result and choose to return radians or degrees, then compute the angle.

## Inverse Tangent Calculator

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## Using the Arctangent Calculator

To use the tool to find the angle from a tangent, enter the ratio and the units you'd like and compute.

**Tangent**- ratio of the opposite side to the adjacent side**Output Degrees or Radians?**- choose to return degrees or radians

Once you're happy, click the "Compute Arctan" button.

**Angle**- the angle you'd input if you wanted to get the tangent you entered

## What is the arctangent or inverse tangent?

Arctangent is the inverse of the tangent, which is the ratio of the opposite side to the adjacent side in a right triangle.

### Arctangent as a formula

Inverse tangent is usually abbreviated as "arctan" or "atan", as in the following equation:

arctan(y)=atan(y)

Where it is the inverse of tangent, or:

x=arctan(y)\\y=tan(x)

*Next, see all the inverse trigonometric functions* or

*trigonometric functions in one tool.*