Trigonometry Calculators

Sine, cosine, tangent, cotangent and their inverse functions, in degrees or radians.

Trigonometry connects the angles of a right triangle to the ratios of its sides. The sine, cosine and tangent calculators take an angle in degrees or radians and return the ratio, and the cotangent calculator does the same for the reciprocal of the tangent. The inverse tools, arcsine, arccosine, arctangent and arccotangent, run the other way: give them a ratio, as a decimal or a fraction, and they return the angle in both degrees and radians.

Pick a single-function page when you want the definition, exact values and a hand calculation for one function, and use the trigonometry calculator when you want to switch between functions on one page. Two checks catch most mistakes. Make sure the angle unit is right before you read the answer, and remember that when you work backwards, sine and cosine only accept values from -1 to 1, because no angle has a sine of 2.

Popular trigonometry calculators

• Trigonometry CalculatorAny trig function or its inverse on one page, in degrees or radians.
• Sine CalculatorSine of an angle, with the definition and a hand calculation.
• Cosine CalculatorCosine of an angle, with a table of exact values.
• Tangent CalculatorTangent of an angle, and how to work it out by hand.

All trigonometry calculators

• Arccos CalculatorType a cosine value, such as 0.5 or 1/3, and read off the angle whose cosine it is, in both degrees and radians. The guide explains the range, identities and a few hand calculations.
• Arccot CalculatorType a cotangent value as a decimal or a fraction and get the matching angle in degrees and radians. The guide explains which angle range this calculator uses and how arccot relates to arctan.
• Arcsine CalculatorGive the calculator a sine value between -1 and 1, as a decimal or a fraction, and it returns the matching angle in both degrees and radians. The guide explains the range, the second solution and how to use the result.
• Arctan CalculatorEnter a tangent value or a slope, as a decimal or a fraction, and read the angle in degrees and in radians. The guide covers the range of arctan, slope-to-angle conversions and a quadrant pitfall.
• Cosine CalculatorType an angle, pick degrees or radians and get its cosine at once. Below you will find what cosine means, a table of exact values and two worked examples.
• Cotangent CalculatorEnter an angle, choose degrees or radians and the calculator returns its cotangent. The guide covers the definition, the angles where cotangent breaks down and a few practical examples.
• Sine CalculatorEnter an angle, choose degrees or radians and read off its sine. The guide below explains what the sine measures, how to find it by hand and where it turns up in practice.
• Tangent CalculatorType an angle, choose degrees or radians and get its tangent straight away. The guide below explains what the tangent measures, how to work it out by hand and where it is used.
• Trigonometry CalculatorChoose a trigonometric function, enter a number and say whether it is in degrees or radians. Inverse functions return the angle in both units at once.