Tangent Calculator

Find the tangent (tan) value of angles in degrees or radians instantly.

What is Tangent?

Tangent (tan) is one of the three primary trigonometric functions, along with Sine and Cosine. In a right-angled triangle, the tangent of an acute angle is defined as the ratio of the length of the opposite side to the length of the adjacent side.

Unlike sine and cosine, which are bounded between -1 and 1, the tangent function can take any real value from negative infinity to positive infinity. It represents the slope of the line created by the angle on the unit circle.

Basic Trigonometric Relationship

Geometric Definitiontan(θ) = Opposite / Adjacent
Analytical Definitiontan(θ) = sin(θ) / cos(θ)

Usage Areas

Engineering & Construction

Tangent is essential for calculating the slope of roads, the pitch of roofs, and the height of structures using shadows.

Physics

The coefficient of friction on an inclined plane is equal to the tangent of the angle of repose ($\mu = \tan\theta$).

Frequently Used Values

Angle (Degree)Angle (Radian)tan(θ)
0°00
30°π/6√3/3 (≈0.577)
45°π/41
60°π/3√3 (≈1.732)
90°π/2Undefined (∞)

Real-World Examples

Calculating Height

Scenario: You are 50 meters from a building and look up at the top at a 60° angle.
Calculation: Height = Distance × tan(60°).
Result: 50 × 1.732 ≈ 86.6 meters.

Road Grade

Scenario: A road rises 10 meters over a horizontal distance of 100 meters.
Calculation: Slope = 10/100 = 0.1. Angle = arctan(0.1).
Result: The road has a grade of about 5.7°.

How to Use This Tangent Calculator

Enter the angle in degrees or radians. The Tangent Calculator returns tan(θ) and may show solution steps. Tangent is the ratio opposite/adjacent in a right triangle and corresponds to slope. Use it for trigonometry, engineering, and geometry. For angles where cos(θ)=0 (e.g. 90°), tangent is undefined. For the inverse (angle from a ratio), use an arctangent calculator. This tool is for informational and educational use only.

When Tangent Calculations Are Used

Tangent is used for slopes, heights and distances (e.g. building height from an angle), and road grades. In calculus, the derivative of tan is sec². This calculator is for general reference only; for high-stakes applications verify with authoritative sources.

In a right triangle, tan(θ) = opposite / adjacent. The tangent function is periodic with period 180° (π radians) and is undefined at 90° and 270° (where cosine is zero). For the inverse (angle from a ratio), use an arctangent calculator. tan(θ) = sin(θ)/cos(θ). This tool is for informational and educational use only.

Limitations

The calculator assumes angles are in degrees or radians as selected. At 90° and 270° (and equivalent in radians), tangent is undefined; the tool may show an error or infinity. For very large angles, reduce modulo 180° (or π) for the equivalent angle. Floating-point precision may cause small errors. This tool is for informational use only; for critical use verify with your curriculum or authority.

For slope m, the angle of inclination is θ = arctan(m). For height at distance d and angle θ, height = d × tan(θ). Tangent is odd: tan(-θ) = -tan(θ). For hyperbolic tangent (tanh), use a dedicated hyperbolic calculator. This tool computes only the circular tangent of an angle. This tool is for informational and educational use only.

Common values: tan(0°)=0, tan(30°)=1/√3, tan(45°)=1, tan(60°)=√3. The tangent function has vertical asymptotes at 90° and 270° (π/2 and 3π/2 radians). In the unit circle, tan(θ) is the y-coordinate divided by the x-coordinate. For sine and cosine use the dedicated calculators; for the inverse (angle from ratio) use an arctangent tool. This calculator is for informational and educational use only.

In surveying and construction, tangent is used to find heights and distances from angles. In physics, slopes and inclines are often expressed as rise over run, which equals tan(θ) when θ is the angle of inclination. This tool gives the numeric value of tan(θ); for symbolic work or step-by-step solutions use your curriculum or a math package. This tool is for informational and educational use only.

Ensure your angle unit (degrees or radians) matches the calculator setting. For angles near 90° or 270°, tangent becomes very large in magnitude; the result may be displayed as undefined or infinity. This calculator is for informational use only; for professional engineering or academic work verify values with authoritative sources. For sine and cosine use the dedicated calculators. Confirm critical values with your curriculum or authority. This tool is for general reference only.

Disclaimer

This tool is for informational use only. It does not replace professional engineering or academic standards. Confirm critical values with your curriculum or authority.

Other Trigonometry Tools

About the Tangent Calculator

A professional tool that calculates trigonometric tangent values of angles with degree and radian support.

Tangent Calculator How to Use?

  1. Enter the angle value
  2. Select the unit (°, rad)
  3. Click the Calculate button
  4. Review the result and solution breakdown

Frequently Asked Questions

What is tangent?

Tangent (tan) is a trigonometric function that represents the ratio of the side opposite a given angle to the side adjacent to it in a right triangle.

For which angles is tangent undefined?

Tangent is undefined (infinite) at angles where the cosine is zero, such as 90°, 270°, and their periodic equivalents (π/2 + kπ radians).

How is tangent related to sine and cosine?

Tangent is the quotient of sine divided by cosine: tan(θ) = sin(θ) / cos(θ).

What is the inverse of tangent?

The inverse function is arctangent (arctan or tan⁻¹), which returns the angle whose tangent is a given number.

Tangent Calculator Features

  • Degree/Radian support
  • Undefined value check
  • Step-by-step solution breakdown
  • High precision

Trigonometry

"Tangent is the numerical language of slope. Infinite at 90 degrees, zero at 0 degrees."