← ← All Tools
中文

🐇 Fibonacci Calculator

Compute the nth Fibonacci number, generate the first n terms, or check whether a number is Fibonacci. BigInt precision with golden-ratio convergence analysis.

F(n) returns the nth Fibonacci number. F(0) = 0, F(1) = 1, F(n) = F(n−1) + F(n−2).

Presets

More tools you might find useful.

🔢
Factorial Calculator
Compute n! (factorial), n!! (double factorial), and !n (subfactorial) with BigInt precision, digit counts, and trailing-zero analysis.
🎯
Final Grade Calculator
Calculate the final exam score you need from your current grade, final weight, and target course grade.
½
Fraction Calculator
Free online fraction calculator supporting arbitrary-operand add/sub/mul/div with integer powers. Natively parses mixed numbers, repeating decimals (0.(3)), percents, and Unicode fraction characters (½ ¼ ⅓). BigInt exact arithmetic with auto-reduce, simultaneous display of improper/mixed/repeating-decimal/percent/LaTeX forms, and step-by-step LCM/combine/GCD explanation plus pie-chart and number-line visuals.
🔗
GCD & LCM Calculator
Calculate GCD and LCM for multiple integers with Extended Euclidean Algorithm and Bézout's identity. Shows step-by-step Euclidean and prime factorization methods.
📐
Geometry Calculator
All-in-one geometry calculator for 25 common 2D shapes and 3D solids — area, perimeter, volume, surface area. Reverse-solve from any known value, with parameter-responsive SVG diagrams, substituted formula steps, per-field unit conversion, and adjustable significant figures / π precision.

Free online Fibonacci calculator supporting nth term F(n) computation, full sequence generation, and Fibonacci number verification. Uses BigInt for exact arbitrary-precision results with scientific notation, digit count, golden-ratio F(n)/F(n−1) convergence analysis, and step-by-step expansion for small values.