#fibonacci

Automatic Fibonacci retracement and extension levels for any stock, index, FX pair, commodity or crypto, computed live from Yahoo Finance candles, no key. Fibonacci levels are the support/resistance map traders draw from a trend's swing high and swing low: after a move, price tends to pull back to the 38.2%, 50% or 61.8% retracement before resuming, and to project to the 127.2%, 161.8% or 261.8% extension as a target. This finds the dominant recent swing automatically and lays the levels out, with where price sits right now. The retracement endpoint detects the swing high and low over a lookback window, works out the trend direction, and returns the retracement levels (0, 23.6, 38.2, 50, 61.8, 78.6, 100%) with their prices — plus which two levels price is currently between and the nearest one. The extension endpoint returns the projection targets beyond the swing (127.2, 141.4, 161.8, 200, 261.8%) in the trend's direction. Both report the swing they were built from so you can see exactly what was measured. This is the Fibonacci-levels cut — a distinct price-level tool, separate from the oscillator and channel indicator feeds (RSI, MACD, Bollinger, SuperTrend, Keltner), from FX pivot points and from the Ichimoku system. Levels are in the instrument's own price; the swing is detected mechanically (highest high / lowest low over the window), not hand-picked. Interval (1d/1wk/1mo) and lookback are configurable. Keyless, nothing stored beyond a short cache.

api.oanor.com/fibonacci-api

Generate famous integer sequences and test membership, with exact big-integer maths. The generate endpoint returns the first N terms of a sequence — Fibonacci, Lucas, prime numbers, triangular, square, cube, factorial, Catalan, pentagonal and tetrahedral numbers, plus parameterised arithmetic (a start and a step), geometric (a start and a ratio) and powers (any base). The contains endpoint tells you whether a given number belongs to a sequence — is 233 a Fibonacci number, is 21 triangular, is 97 prime, is 720 a factorial — using fast closed-form tests for primes, squares, cubes, triangular, pentagonal and Fibonacci numbers and an exact search for the rest, and it returns the term index where it is known. Because everything is computed with arbitrary-precision integers, terms beyond the usual floating-point limit are returned exactly as decimal strings and never overflow. It runs entirely locally, so it is instant, deterministic and private. Ideal for education and maths tooling, coding challenges and puzzles, test-data generation, recreational mathematics and number-theory experiments. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This generates and tests integer sequences; to factorize a single number or get its divisors use a number-theory API.

api.oanor.com/sequences-api