Fibonacci Calculator

Compute Fibonacci numbers quickly and easily.

Calculate Fibonacci Number

Enter a non-negative integer to find its Fibonacci sequence value.

Enter Number
About the Fibonacci Sequence

The Fibonacci sequence is a series of numbers where each number is the sum of the two preceding ones, starting with 0 and 1. This calculator computes the \( n \)-th Fibonacci number using the recurrence relation:

  • \( F(0) = 0 \)
  • \( F(1) = 1 \)
  • \( F(n) = F(n-1) + F(n-2) \) for \( n \geq 2 \)

For example, the sequence begins: 0, 1, 1, 2, 3, 5, 8, 13, 21, and so on.