Math · Functions

Inverse Function Calculator

Solve x = f⁻¹(y) numerically for almost any function, check whether f is invertible on an interval, and verify the result.

Function f(x)

Value y to invert

Search lower bound

Search upper bound

x = f⁻¹(y)

Monotonicity on interval

Inverse exists?

Verification f(f⁻¹(y))

f⁻¹(y) via y = f(x)

Definition: f is invertible on an interval if it is strictly monotonic (always increasing or always decreasing) there.
Numeric method: find the root of g(x) = f(x) − y = 0 by bisection on the search interval.
Supported syntax: x, ^, sin/cos/tan, exp, log (natural), sqrt, abs, pi, e.

Any invertible function

Linear, exponential, logarithmic, trigonometric — solve the inverse numerically.

Monotonicity check

Sampling the interval tells you if an inverse exists before you solve.

Built-in verification

Every answer is checked with f(f⁻¹(y)) ≈ y.

Adjustable search range

Widen the bounds for multiple roots or steep functions.

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