Fibonacci Approximator

Chrome Extension · Manifest V3 · JavaScript · 2026

A minimal, privacy-first Manifest V3 browser extension for Google Chrome and Microsoft Edge.

Enter a number and get its adjacent (or nearest bounding) Fibonacci values.

Fibonacci Approximator interval calculation

Fibonacci Approximator exact match result

How it works

Given an integer input, the extension returns two Fibonacci values: an exact match in the sequence, an intermediate bounding interval, or zero.

100% local. No data collection. The extension only requests temporary access to the active tab to inject the user interface securely. The number you type is evaluated entirely locally, in-memory, and discarded when the overlay closes.