Why does tan 90° show 'undefined'?

Tangent equals sin/cos. At 90° cosine is zero, so the division is undefined. The same thing happens at 270° and every odd multiple of 90°.

What is the difference between sec and csc?

Secant is the reciprocal of cosine (1/cos), and cosecant is the reciprocal of sine (1/sin).

Should I use degrees or radians?

Use whatever your problem requires. In calculus and physics, radians are standard. In everyday geometry and navigation, degrees are more common.

How accurate are the results?

The calculator uses the browser’s built-in Math library, which works in 64-bit floating-point precision — more than enough for virtually any practical application.

Trigonometric Functions Calculator

Calculate sine, cosine, tangent, cotangent, secant, and cosecant for any angle in degrees or radians.

Angle

Unit

Decimal Places

Features

All six functions

sin, cos, tan, cot, sec, and csc computed in one go

Degrees or radians

Toggle the input unit to match your problem

Special-angle buttons

Quick access to 0°, 30°, 45°, 60°, 90°, and others

Decimal precision

Choose how many digits to display (0–10)

How to use this tool

1
Enter an angle — Type a number in the input field
2
Choose the unit — Select Degrees or Radians
3
Read all values — Every trig function for that angle appears in a table
4
Fine-tune decimals — Adjust the precision slider if you need more or fewer digits

Common uses

Structural engineering

Resolve forces into components when analysing beams and trusses

Physics labs

Calculate wave amplitudes, projectile angles, and pendulum periods

Surveying & navigation

Find bearings, distances, and elevations from angle measurements

Maths revision

Verify trig identities and check exam answers quickly

Frequently asked questions

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