Triangle Trigonometry Calculator – Solve Angles & Sides
Evaluate sin, cos, tan and inverse functions in degrees or radians.
About the Trigonometry Calculator
What is the Trigonometry Calculator?
A trigonometry calculator evaluates sine, cosine, tangent and their inverses in degrees or radians.
Why use this calculator?
Angles drive navigation, construction, sound waves and computer graphics. Having the functions and unit switching instantly is a small superpower.
How to use it
- Pick the function (sin, cos, tan, asin, acos, atan).
- Enter the value.
- Choose degrees or radians and read the answer.
Formula
Standard function definitions; inverse functions return the principal branch.
For tan input near 90° note the function is undefined exactly at 90°.
Frequently Asked Questions
Degrees or radians?
Degrees suit everyday angles; radians are standard in calculus and programming. Choose whichever your problem uses.
Why does tan(90°) blow up?
Cosine hits zero at 90°, and tan = sin/cos, so the ratio becomes undefined (approaches infinity).
What order of operations does this use?
It follows standard PEMDAS/BODMAS rules: parentheses, exponents, multiplication and division, then addition and subtraction.
How precise are the answers?
The calculator uses double-precision floating-point math (about 15 significant digits) and rounds the display. For exact symbolic results use dedicated algebra software.
Can I enter negative numbers or decimals?
Yes. Negative values, decimals and very large or small numbers are all supported unless a field says otherwise.
What does it mean if I get an error?
Errors usually mean an invalid input, such as division by zero or a negative value where only positives make sense. Check your entries and try again.
Which units should I use?
Use one consistent unit for every input. The result will be in that unit (or its square or cube for area and volume).
How is area different from perimeter?
Perimeter is the distance around a shape; area is the space it covers. Perimeter is measured in units, area in square units.
Does the orientation of the shape matter?
No. Area, perimeter and volume depend only on the dimensions, not on how the shape is rotated or positioned.
Is this calculator free to use?
Yes. Every calculator on this site is completely free, with no hidden fees, no subscriptions and no limits on how many times you can use it.