Fibonacci Generator

Overview

The Fibonacci Generator API computes Fibonacci sequence values along with derived statistics — a sum, the trailing 5 consecutive-value ratios, and the most recent ratio as an approximation of the golden ratio. It accepts two mutually-exclusive modes: `count` for a fixed-length response, or `maxvalue` for every Fibonacci number up to a numeric ceiling. An optional `startfrom` parameter advances the generator before emission begins. All arithmetic uses standard JavaScript Number type on the server, so values above Number.MAX_SAFE_INTEGER (around the 79th Fibonacci number) cannot be represented exactly — the precision ceiling is end-to-end. The ratios array is always truncated to the last 5 entries regardless of sequence length, and each ratio is rounded to 6 decimal places.

Endpoint

One host, one path per API. The block below shows this call in four languages; every one of them is the same HTTP request. Making requests covers the timeouts, retries and parameter rules that apply to all of them. The SDKs wrap the same call in a typed client.

curl "https://api.apiverve.com/v1/fibonaccigenerator?count=10&startfrom=0" \
  -H "x-api-key: your_api_key_here"

const res = await fetch('https://api.apiverve.com/v1/fibonaccigenerator?count=10&startfrom=0', {
  headers: { 'x-api-key': 'your_api_key_here' },
});

if (!res.ok) throw new Error(`${res.status} ${await res.text()}`);

const { data } = await res.json();
console.log(data);

import requests

res = requests.get(
    "https://api.apiverve.com/v1/fibonaccigenerator?count=10&startfrom=0",
    headers={"x-api-key": "your_api_key_here"},
    timeout=15,
)
res.raise_for_status()

print(res.json()["data"])

package main

import (
	"fmt"
	"io"
	"net/http"
)

func main() {
	req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/fibonaccigenerator?count=10&startfrom=0", nil)
	req.Header.Set("x-api-key", "your_api_key_here")

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()

	out, _ := io.ReadAll(res.Body)
	fmt.Println(string(out))
}

Replace your_api_key_here with the key from your dashboard. When the inputs arrive as a list rather than one at a time, batch requests run up to 200 of them through this same API in a single call.

Authentication

Send your key in the x-api-key header. That is the only auth step — there is no token exchange and no per-endpoint scope to configure. Authentication covers creating, rotating and revoking keys.

Parameters

Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them.

Response

Every API returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape. Response format covers the envelope, the other output formats and how premium fields are withheld.

{
  "status": "ok",
  "error": null,
  "data": {
    "sequence": [
      0,
      1,
      1,
      2,
      3,
      5,
      8,
      13,
      21,
      34
    ],
    "count": 10,
    "start_from": 0,
    "first_value": 0,
    "last_value": 34,
    "sum": 88,
    "ratios": [
      1.666667,
      1.6,
      1.625,
      1.615385,
      1.619048
    ],
    "golden_ratio_approximation": 1.619048
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change. Error handling covers the full status list and which of them are worth retrying.

Use cases

Math Education

Teach Fibonacci sequences and golden ratio concepts in educational applications and tools

Algorithm Testing

Generate test data for algorithms and performance testing using Fibonacci sequences

Visual Design

Apply Fibonacci ratios and golden ratio proportions in design and layout calculations

Data Analysis

Use Fibonacci numbers in technical analysis, trading algorithms, and pattern recognition

Other ways to use Fibonacci Generator

Set up Fibonacci Generator on APIVerve, or reach the same source a different way. Your APIVerve account and credits work on all of them — one key, one balance.

Related

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