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Cotangent Calculator.

Calculate cotangent for an angle entered in degrees.

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01

Set your values

Results update as you type.

Angle (rad): 0.785398 rad

Angle (rad)

0.000000rad
Cotangent: 1

Cotangent

0.000000

Results update automatically as you type.

Use Cases

Solve trigonometry problems

Quickly find the cotangent of an angle for homework, exam prep, or engineering calculations without manual computation.

Example: Find cot(45°) = 1

Check manual calculations

Verify your own cotangent calculations for accuracy, especially when working with non-standard angles.

Example: Check cot(30°) ≈ 1.732

Frequently Asked Questions

What is cotangent and how is it calculated?
Cotangent (cot) is the reciprocal of tangent. For an angle in a right triangle, cot = adjacent side / opposite side. In terms of sine and cosine, cot = cos(θ) / sin(θ). This calculator computes cot for an angle you enter in degrees.
Can I enter any angle in degrees?
Yes, you can enter any real number in degrees, including negative angles and angles greater than 360°. The calculator will compute the cotangent value. Note that cotangent is undefined for angles where sine is zero (e.g., 0°, 180°, 360°).
What is the range of cotangent values?
Cotangent values can be any real number from negative infinity to positive infinity. For angles between 0° and 180°, cot is positive for acute angles and negative for obtuse angles. The calculator gives the exact decimal value.

Tips & Common Mistakes

Tips

  • Remember that cot(θ) = 1/tan(θ). If you know the tangent, you can find cotangent by taking its reciprocal.
  • For angles like 0°, 180°, and 360°, cotangent is undefined because sine is zero. The calculator may show an error or infinity.
  • Use the calculator to explore how cotangent changes with angle: it decreases from positive infinity to negative infinity as the angle goes from 0° to 180°.
  • When entering angles, ensure you are using degrees, not radians, as this calculator is designed for degree input.

Common Mistakes to Avoid

  • Confusing cotangent with tangent: cot(θ) is the reciprocal, not the same as tan(θ). For example, cot(45°) = 1, not 1.414.
  • Forgetting that cotangent is undefined at multiples of 180° (0°, 180°, 360°, etc.) because sine is zero.
  • Using radians instead of degrees: if you enter an angle in radians, the result will be incorrect because the calculator expects degrees.

Last updated: August 13, 2026