Inverse Trig Calculator
Calculate arcsin, arccos, or arctan of a value, with the result shown in both degrees and radians.
arcsin (sin⁻¹)(0.5) in degrees
30.0000°
arcsin (sin⁻¹)(0.5) in radians
0.523599
Recommended Settings
Pro Tips
- •Inverse trig functions answer 'what angle produces this ratio?' - arcsin(0.5) asks what angle has a sine of 0.5
- •arcsin and arccos are only defined for inputs between -1 and 1, since sine and cosine never produce values outside that range
- •arctan accepts any real number, since the tangent function's range covers all real numbers
- •The principal value is always returned - the standard convention range is -90° to 90° for arcsin and arctan, and 0° to 180° for arccos
Most Popular
Most people use arcsin or arccos to find an angle in a right triangle when they know two side lengths
When to Use This Tool
Find the angle corresponding to a known sine, cosine, or tangent ratio.
Determine a triangle's angle when you know the ratio of two of its sides.
Calculate an angle of incidence, elevation, or direction from a known ratio.
Verify an inverse trig calculation from another source.
How It Works
Validate that the input is within the valid domain for the selected inverse function
Compute the angle in radians using the browser's built-in inverse trigonometric functions
Convert the radian result to degrees for display alongside the original radian value
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Files never leave your device. All processing happens locally in your browser.
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Open Source
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Frequently Asked Questions
Why is arcsin only defined between -1 and 1?
Because sine itself only ever produces values between -1 and 1, there's no angle whose sine equals a number outside that range, so arcsin has no valid input beyond it.
What's the difference between degrees and radians here?
Both represent the same angle, just in different units - degrees divide a full circle into 360 parts, while radians measure the angle by arc length relative to the radius, with a full circle equal to 2π radians.
Why does arctan accept any number?
Tangent's range covers all real numbers, from negative infinity to positive infinity, so arctan can accept any real number as input and always returns a valid angle.
Is my data sent anywhere?
No. All calculations happen locally in your browser.