Tangent Angle Calculator

Calculate tangent values from angles or triangle sides with detailed explanations

Calculate Tangent

Enter the angle value

Choose the input unit for your angle

Tangent Results

0.000000
Tangent Value
0
0.00°
Angle in Degrees
Quadrant I (positive)
0.000000
Radians
0.0000π
Pi Radians

Calculation: tan(0.00°) = 0.000000

Exact Value: tan(0°) = 0

Period: Tangent has a period of π radians (180°)

Common Tangent Values

Special Angles

tan(0°) = 0

tan(30°) = 1/√3 ≈ 0.577

tan(45°) = 1

tan(60°) = √3 ≈ 1.732

tan(90°) = undefined

Triangle Example

Given: Opposite = 21, Adjacent = 8

Calculation: tan(θ) = 21/8 = 2.625

Angle: θ = arctan(2.625) ≈ 69.1°

Verification: tan(69.1°) ≈ 2.625

Tangent Function Properties

1

Definition

tan(θ) = opposite/adjacent

Also: tan(θ) = sin(θ)/cos(θ)

2

Period

π radians (180°)

Repeats every 180°

3

Asymptotes

At odd multiples of 90°

..., -90°, 90°, 270°, ...

Quadrant Analysis

Quadrant I

0° to 90°

Positive

Quadrant II

90° to 180°

Negative

Quadrant III

180° to 270°

Positive

Quadrant IV

270° to 360°

Negative

Quick Tips

Tangent is the ratio of opposite to adjacent sides

tan(45°) = 1 is a key reference value

Function is undefined at 90°, 270°, etc.

Period is π radians (180°)

Understanding Tangent Function

What is Tangent?

The tangent of an angle in a right triangle is the ratio of the length of the opposite side to the length of the adjacent side. It's one of the fundamental trigonometric functions and can also be expressed as the ratio of sine to cosine: tan(θ) = sin(θ)/cos(θ).

Key Properties

  • Domain: All real numbers except odd multiples of π/2
  • Range: All real numbers (-∞, +∞)
  • Period: π radians (180°)
  • Odd Function: tan(-θ) = -tan(θ)

Practical Applications

  • Engineering: Slope calculations and structural analysis
  • Physics: Angle of incidence and trajectory calculations
  • Navigation: Bearing and heading computations
  • Architecture: Roof pitch and ramp angle design
  • Surveying: Measuring angles and distances

Asymptotes

Important: The tangent function has vertical asymptotes (undefined values) at angles where cosine equals zero: ..., -90°, 90°, 270°, 450°, ...

Memory Tip: SOH-CAH-TOA helps remember: Tangent = Opposite/Adjacent