Arctan Calculator (Inverse Tangent)

Calculate inverse tangent (arctangent) values in degrees and radians with step-by-step explanations

Calculate Inverse Tangent

Domain: All real numbers (-∞, +∞)

Range: (-90°, 90°) or (-π/2, π/2) rad

Calculation Results

0.000000°
Degrees
0.000000
Radians

✓ Special angle recognized: arctan(0) =

Calculation: arctan(0) = 0.000000°

Exact values: Degrees: 0.000000°, Radians: 0.000000 rad

Range: Arctan output is always between -90° and 90° (-π/2 and π/2 radians)

Related Trigonometric Values

sin(θ)
0.000000
cos(θ)
1.000000
tan(θ)
0.000000

Where θ = arctan(0) = 0.000000°

Common Arctan Values

Input (x)arctan(x) Degreesarctan(x) RadiansExact Value
000
√3/3 ≈ 0.57730°π/6 ≈ 0.524π/6
145°π/4 ≈ 0.785π/4
√3 ≈ 1.73260°π/3 ≈ 1.047π/3
-√3/3 ≈ -0.577-30°-π/6 ≈ -0.524-π/6
-1-45°-π/4 ≈ -0.785-π/4
-√3 ≈ -1.732-60°-π/3 ≈ -1.047-π/3

Arctan Properties

Domain: All real numbers (-∞, +∞)

Range: (-π/2, π/2) or (-90°, 90°)

arctan(-x) = -arctan(x) (odd function)

tan(arctan(x)) = x for all x

As x → ±∞, arctan(x) → ±π/2

Key Formulas

Basic Definition

If tan(θ) = x, then θ = arctan(x)

Derivative

d/dx[arctan(x)] = 1/(1 + x²)

Integral

∫arctan(x)dx = x·arctan(x) - ½ln(1+x²) + C

Addition Formula

arctan(x) + arctan(y) = arctan((x+y)/(1-xy))

Quick Tips

arctan(1) = 45° = π/4 radians

arctan(0) = 0° = 0 radians

arctan is the inverse of the tan function

Used to find angles in right triangles

Understanding Inverse Tangent (Arctan)

What is Arctan?

The arctangent (arctan) is the inverse function of the tangent. If tan(θ) = x, then θ = arctan(x). It answers the question: "What angle has a tangent equal to this value?"

Domain and Range

  • Domain: All real numbers (-∞, +∞)
  • Range: (-π/2, π/2) or (-90°, 90°)
  • Unlike tangent, arctan is defined for all real numbers

Mathematical Properties

Odd Function

arctan(-x) = -arctan(x)

Horizontal Asymptotes

lim(x→+∞) arctan(x) = π/2
lim(x→-∞) arctan(x) = -π/2

Monotonicity

Strictly increasing function

Practical Applications

Navigation

Calculate bearing angles from coordinate differences

Engineering

Find angles of inclination, slopes, and gradients

Physics

Calculate angles in vector problems and projectile motion