About this calculator
Enter an angle in degrees or radians and get its sin, cos and tan, plus cosec, sec and cot.
For the common angles (0°, 30°, 45°, 60°, 90° and their multiples) it also shows the exact value, such as sin 30° = 1/2.
Worked examples
Real numbers, worked out by the same calculator. Press “Use these numbers” to try one above.
30 degrees
- sin
- 0.5 (exactly 1/2)
- cos
- 0.866025 (exactly √3/2)
- tan
- 0.57735 (exactly 1/√3)
- cosec (1 ÷ sin)
- 2
- sec (1 ÷ cos)
- 1.154701
- cot (1 ÷ tan)
- 1.732051
- Angle in degrees
- 30
- Angle in radians
- 0.523599
For 30°: sin = 0.5, cos = 0.866025 and tan = 0.57735.
Show the working
- Work in degrees: 30° = 0.523599 radians.
- sin = 0.5, cos = 0.866025.
- tan = sin ÷ cos = 0.57735.
45 degrees
- sin
- 0.707107 (exactly √2/2)
- cos
- 0.707107 (exactly √2/2)
- tan
- 1 (exactly 1)
- cosec (1 ÷ sin)
- 1.414214
- sec (1 ÷ cos)
- 1.414214
- cot (1 ÷ tan)
- 1
- Angle in degrees
- 45
- Angle in radians
- 0.785398
For 45°: sin = 0.707107, cos = 0.707107 and tan = 1.
Show the working
- Work in degrees: 45° = 0.785398 radians.
- sin = 0.707107, cos = 0.707107.
- tan = sin ÷ cos = 1.
π ÷ 3 radians (1.0472)
- sin
- 0.866025
- cos
- 0.5
- tan
- 1.732051
- cosec (1 ÷ sin)
- 1.154701
- sec (1 ÷ cos)
- 2
- cot (1 ÷ tan)
- 0.57735
- Angle in degrees
- 60
- Angle in radians
- 1.047198
For 60°: sin = 0.866025, cos = 0.5 and tan = 1.732051.
Show the working
- Work in degrees: 60° = 1.047198 radians.
- sin = 0.866025, cos = 0.5.
- tan = sin ÷ cos = 1.732051.
What sin, cos and tan mean
In a right-angled triangle, for an angle θ: sin θ = opposite ÷ hypotenuse, cos θ = adjacent ÷ hypotenuse and tan θ = opposite ÷ adjacent. The memory aid SOH-CAH-TOA captures this. On the unit circle, cos and sin are the x and y coordinates of the point at angle θ.
Exact values to remember
| Angle | sin | cos | tan |
|---|---|---|---|
| 0° | 0 | 1 | 0 |
| 30° | 1/2 | √3/2 | 1/√3 |
| 45° | √2/2 | √2/2 | 1 |
| 60° | √3/2 | 1/2 | √3 |
| 90° | 1 | 0 | undefined |
When tan is undefined
tan θ = sin θ ÷ cos θ, and cos is zero at 90°, 270° and every angle 180° apart from those, so tan has no value there. The same is true of sec at those angles, and of cosec and cot where sin is zero.
Frequently asked questions
Is my calculator in degrees or radians?
This one lets you choose. Scientific calculators have a DEG/RAD switch; using the wrong one is the most common cause of wrong trig answers.
What is sin 30 degrees?
Exactly 1/2, or 0.5.
What is tan 90 degrees?
It is undefined, because cos 90° is 0 and you can't divide by zero.
How do I convert degrees to radians?
Multiply by π ÷ 180. The angle converter does it for you.
Formulas tested against hand-worked answers. Last reviewed 29 September 2026. These calculators do arithmetic only; they are not financial, tax or legal advice.