Trigonometry Calculator
Calculate sine, cosine, tangent, inverse trig functions, and identities with a DEG/RAD online scientific calculator.
Trigonometry calculator for sin, cos, tan, DEG, and RAD
Use this trigonometry calculator for sine, cosine, tangent, and inverse trig functions.
Switch between DEG and RAD mode depending on whether your angle is in degrees or radians.
Features
- sin, cos, tan, asin, acos, and atan.
- DEG/RAD toggle for angle mode.
- Trig expressions with powers and fractions.
- Useful for identities such as sin²(x)+cos²(x).
- Undefined tangent angles are reported as errors instead of misleading huge numbers.
Example expressions
\sin(30^\circ)\cos(60^\circ)\tan(45^\circ)\sin(30^\circ)^2+\cos(30^\circ)^2\operatorname{asin}(0.5)\operatorname{atan}(1)
How to use this calculator
- Choose DEG for degree inputs or RAD for radian inputs.
- Insert sin, cos, tan, asin, acos, or atan from the button panel.
- Use powers or fractions around trig functions when checking identities.
Common input mistakes
- tan(90°) is undefined and should not be treated as a normal finite result.
- cos(pi) should be calculated in RAD mode, not DEG mode.
- Inverse trig functions return degrees in DEG mode and radians in RAD mode.
FAQ
Should I use DEG or RAD?
Use DEG for angles measured in degrees and RAD for radians.
Does it support inverse trigonometry?
Yes. The panel includes asin, acos, and atan.
Can I square a trig function?
Yes. Enter the trig function and then use ^2 or the x² button.
Why does tan(90°) show an error?
Tangent is undefined when cosine is zero, so the calculator reports it as an undefined value.