Calculate arctan (tan⁻¹) of any value. Get results in degrees, radians, gradians, and turns. Includes atan2 mode, common values table, and visual range indicator.
The **Inverse Tangent Calculator** computes arctan(x) — the angle whose tangent equals x — and returns the result in degrees, radians, gradians, and turns. The arctan function is essential for converting a ratio or slope into an angle, one of the most common operations in trigonometry, physics, and engineering.
The standard arctan function returns values in the range (−90°, 90°), but many applications require a full four-quadrant angle. This calculator offers an **atan2 mode** that takes both a y-value and an x-value to return an angle in the full (−180°, 180°] range, correctly placing the result in the appropriate quadrant.
For each result the tool shows the general solution — all angles sharing the same tangent — using the formula θ = arctan(x) + n·180° for any integer n. It also verifies correctness by computing tan(result) and showing that it equals the original input.
The calculator includes preset buttons for common inverse tangent inputs, a visual indicator showing where the result falls within the arctan range, and a comprehensive reference table of standard arctan values. Whether you need to convert a slope to a heading, find a phase angle in electronics, or check an answer on a trig exam, this calculator handles it instantly.
Inverse Tangent Calculator (tan⁻¹ / arctan) — Degrees & Radians helps you avoid repetitive setup mistakes when solving trigonometric and coordinate-geometry problems. Instead of recalculating conversions, signs, and edge cases by hand, you can test inputs immediately, inspect intermediate values, and confirm final answers before submitting work or using numbers in downstream calculations. It surfaces key outputs like Result (degrees), Result (radians), Result (gradians) in one pass.
arctan(x) returns θ such that tan(θ) = x and −90° < θ < 90°. atan2(y, x) returns θ in (−180°, 180°] identifying the correct quadrant. General solution: θ + n·180° for any integer n.
Result: 45°
Using value=1, unit=degrees, the calculator returns 45°. This example mirrors the calculator's live computation flow and is useful for checking manual steps and unit handling.
This calculator is tailored to inverse tangent calculator (tan⁻¹ / arctan) — degrees & radians workflows, including common input modes, unit handling, and special-case behavior. It is designed for fast checking during homework, exam preparation, technical drafting, and coding tasks where trigonometric consistency matters.
Use the primary result together with supporting outputs to verify direction, magnitude, and validity. Cross-check against known identities or geometric constraints, and confirm that angle ranges, sign conventions, and domain restrictions are satisfied before using the numbers elsewhere.
A reliable way to improve is to solve once manually, then verify with the calculator and explain any mismatch. Repeat this on varied examples and edge cases. The built-in preset scenarios for quick trials, comparison tables for side-by-side validation, visual cues that make trends and quadrants easier to read help you build pattern recognition and reduce sign or conversion errors over time.
Arctan is the inverse tangent function. Given a value x, arctan(x) returns the angle whose tangent is x, restricted to the interval (−90°, 90°).
arctan(x) takes a single ratio and returns an angle in (−90°, 90°). atan2(y, x) takes two separate values and returns an angle in (−180°, 180°], correctly identifying all four quadrants.
arctan(0) = 0°. The tangent function equals zero at 0°, 180°, 360°, etc., but the principal value is 0°.
No — by definition the principal value of arctan is always in (−90°, 90°). For angles outside this range, add multiples of 180° or use atan2.
If a line has slope m, the angle it makes with the horizontal is θ = arctan(m). For example, slope 1 → 45°, slope 0.5 → ≈ 26.57°.
Since tangent has period 180°, if arctan(x) = θ then the general solution is θ + n·180° for any integer n. This provides clearer practical guidance for reliable use.