Sine Calculator

Calculate Sine (sin(x))

Find the sine of an angle using the sin calculator below. Start by entering the angle in degrees or radians.

Please enter a valid number.

Sine Diagram

90° 180° 270° θ sin(θ)

How to Calculate Sine

The sine function, denoted as sin(x), is a fundamental trigonometric function that relates the angles of a right triangle to the ratios of the lengths of its sides. It is widely used in various fields of mathematics, physics, and engineering.

Formula

The sine of an angle θ in a right-angled triangle is defined as:

\[ \sin(\theta) = \frac{\text{opposite}}{\text{hypotenuse}} \]

Where:

  • sin(θ) is the sine of the angle θ
  • opposite is the length of the side opposite to the angle θ
  • hypotenuse is the length of the longest side of the right triangle
  • θ is the angle in radians

Calculation Steps

  1. Ensure the angle is in radians. If it's in degrees, convert it to radians by multiplying by π/180°.
  2. Use a calculator or trigonometric tables to find the sine value of the angle.
  3. The result will be a value between -1 and 1, inclusive.

Example

Let's calculate sin(30°):

  1. Convert 30° to radians: 30° × (π/180°) = π/6 radians
  2. Calculate sin(π/6) ≈ 0.5

Therefore, sin(30°) = 0.5

Visual Representation

90° 180° 270° θ = 30° sin(30°) = 0.5

This diagram illustrates sin(30°). The blue line represents the angle of 30°, and the red line shows the sine value of 0.5 on the y-axis.