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Fibonacci Calculator.
Calculate an exact Fibonacci term or generate a bounded sequence from F₀ = 0 and F₁ = 1.
Set your values
Results update as you type.
Whole number from 0 to 10,000.
Terms from F₀, up to 100.
Breakdown
Sequence from F₀
0, 1, 1, 2, 3, 5, 8, 13, 21, 34
Fₙ = Fₙ₋₁ + Fₙ₋₂ for n ≥ 2. Values are calculated exactly; no floating-point rounding is used.
How to Use
The Fibonacci sequence starts F₀ = 0, F₁ = 1; each following term is the sum of the two before it.
Exact BigInt output is capped at n = 10,000; sequences are capped at 100 terms so the page stays responsive.
FAQs
What are the first Fibonacci numbers?
Using the zero-based convention, F₀ = 0, F₁ = 1, and each next term is the sum of the two preceding terms.
Are the results rounded?
No. The calculator uses exact integer arithmetic and caps the input so the browser stays responsive.