Sin Theta Calculator

Calculate sine of any angle (θ) in degrees, radians, or π radians with detailed analysis

Calculate sin(θ)

Enter any angle value (positive or negative)

sin(θ) Results

0.000000
sin(0°)
Exact value: 0
Normalized angle:0.00°
Quadrant:1
Reference angle:0.00°
Sign:zero (at 0°, 180°, 360°, etc.)

Unit Circle Position

Red line shows sin(θ) = y-coordinate (0.000)

Related Trigonometric Values

cos(θ):
1.000000
tan(θ):
0.000000
sin²(θ) + cos²(θ):
1.000000

Common Sine Values

Angle (degrees)Angle (radians)sin(θ) - Exactsin(θ) - Decimal
0°000.0000
30°π/61/20.5000
45°π/4√2/20.7071
60°π/3√3/20.8660
90°π/211.0000
120°2π/3√3/20.8660
135°3π/4√2/20.7071
150°5π/61/20.5000
180°π00.0000
270°3π/2-1-1.0000
360°00.0000

Sine Signs by Quadrant

Quadrant I
0° to 90°
+
Quadrant II
90° to 180°
+
Quadrant III
180° to 270°
-
Quadrant IV
270° to 360°
-

Sine Function Properties

1

Periodic

Period = 360° (2π rad)

2

Range

-1 ≤ sin(θ) ≤ 1

3

Odd Function

sin(-θ) = -sin(θ)

4

Unit Circle

y-coordinate on unit circle

Quick Tips

sin(0°) = 0, sin(90°) = 1, sin(180°) = 0, sin(270°) = -1

Sine is positive in quadrants I and II

sin(θ + 360°) = sin(θ) for any angle

sin²(θ) + cos²(θ) = 1 (Pythagorean identity)

Understanding the Sine Function

What is sin(θ)?

The sine function (sin) is one of the fundamental trigonometric functions. For any angle θ, sin(θ) represents the y-coordinate of the point where the terminal side of the angle intersects the unit circle (a circle with radius 1 centered at the origin).

Unit Circle Definition

On the unit circle, if we draw a line from the origin at angle θ from the positive x-axis, the sine of θ equals the y-coordinate of where this line meets the circle. This geometric interpretation helps us understand why sine values range from -1 to 1.

Key Properties

  • Domain: All real numbers
  • Range: [-1, 1]
  • Period: 360° or 2π radians
  • Symmetry: Odd function (sin(-θ) = -sin(θ))

Remember: Sine is positive in quadrants I and II, negative in quadrants III and IV.

Applications of sin(θ)

Physics

Wave motion, oscillations, alternating current, projectile motion

Engineering

Signal processing, structural analysis, electrical engineering

Navigation

GPS calculations, astronomy, surveying, maritime navigation