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Math

Inverse Trig Calculator

Instantly find arcsin, arccos, and arctan in degrees and radians

Input

For arcsin and arccos, x must be between −1 and 1. Arctan accepts any real number.

Quick examples

Results

arcsin (sin⁻¹)

Input range: [−1, 1] | Output: [−90°, 90°]

Degrees

30°

30.0000000000°

Radians

0.523599 rad

0.5235987756 rad

0.166667 π

arccos (cos⁻¹)

Input range: [−1, 1] | Output: [0°, 180°]

Degrees

60°

60.0000000000°

Radians

1.047198 rad

1.0471975512 rad

0.333333 π

arctan (tan⁻¹)

Input range: all real numbers | Output: (−90°, 90°)

Degrees

26.565051°

26.5650511771°

Radians

0.463648 rad

0.4636476090 rad

0.147584 π

Inverse Trig Reference

xarcsin(x)arccos(x)arctan(x)
−1−90°180°
−√3/2−60°150°
−√2/2−45°135°
−1/2−30°120°
090°
1/230°60°
√2/245°45°
√3/260°30°
190°

All values shown in degrees. Conversion: degrees = radians × (180 / π).

About

The inverse trig calculator computes arcsin, arccos, and arctan for any input value, returning results in both degrees and radians simultaneously. Whether you need sin inverse for a geometry problem, arccos for a dot-product angle, or arctan to convert a slope into degrees, this tool handles all three inverse trigonometric functions instantly — no formula lookup required.

FAQ
What is the domain (valid input range) for each inverse trig function?+

Arcsin and arccos only accept inputs between −1 and 1 (inclusive), because sine and cosine values always fall in that range. Arctan has no such restriction — it accepts any real number, including very large values, returning an angle approaching ±90°.

How do I convert the radian result to degrees?+

Multiply the radian value by 180 divided by π (approximately 57.2958). The calculator does this automatically and shows both units side by side, so no manual conversion is needed.

Why does arcsin(0.5) equal 30° and not 150°?+

Inverse trig functions are defined to return a single principal value. Arcsin always returns an angle in the range [−90°, 90°], so arcsin(0.5) = 30°. The angle 150° also has a sine of 0.5 but lies outside the principal range — you would need to use the supplementary angle identity if your problem requires it.

What is the difference between arcsin and arccos for the same input?+

For any x in [−1, 1], arcsin(x) + arccos(x) = 90° (π/2 radians). This complementary relationship means the two angles always add up to a right angle. For example, arcsin(0.5) = 30° and arccos(0.5) = 60°, which sum to 90°.

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