M
API Matrix

Numbers API

⭐ Beginner's Pick Science & Math / No Auth Required Beginner HTTP
Free to Use Varies (check documentation)
74 Score
Grade B
Visit Official Site Compare Alternatives

Overview

Numbers API (numbersapi.com) returns interesting facts about numbers — mathematical, date-based, year-based, or trivia facts. It requires no authentication and is incredibly simple to use: just put a number in the URL and get a plain text sentence back. It is one of the easiest APIs for beginners to try and great for adding fun number facts to any project.

💡

Beginner Tip

By default the API returns plain text, but add ?json to any URL to get a structured JSON response with extra fields — much easier to work with in code.

Available Data

Use case: Integrate facts about numbers data into web and mobile applications
Numbers data via REST API
JSON-formatted response data
Freely accessible without authentication

Example Response

JSON Response 
{
  "status": "success",
  "data": {
    "result": "Data from Numbers",
    "description": "Facts about numbers",
    "timestamp": "2025-01-15T10:00:00Z"
  }
}

Field Reference

text The interesting fact about the number as a human-readable sentence.
found True if a specific fact exists for this number; false if a default/generic fact was returned.
number The number you queried, echoed back for reference.
type The category of fact returned: "trivia", "math", "date", or "year".

Implementation Example 

const url = "http://numbersapi.com/";
const response = await fetch(url);
if (!response.ok) throw new Error(`Request failed: ${response.status}`);
const data = await response.json();
console.log(data);

What Can You Build?

Note: These code examples are AI-generated and unverified. Always refer to the official API documentation for accurate usage.

Common Errors & Troubleshooting

Response is just plain text, not JSON The ?json query parameter was not included in the request URL.
✓ Append ?json to any Numbers API URL to receive a structured JSON object instead of a plain text string.
"found": false in response The API does not have a specific fact for that number, so it returned a generic one.
✓ This is normal behavior — the API always returns a fact, but "found: false" means it was a default fallback rather than a specific fact.
HTTP blocked by browser Some environments and browsers block insecure HTTP requests.
✓ Note that numbersapi.com uses HTTP not HTTPS. For secure contexts, proxy requests through your own HTTPS server.

Matrix Score Breakdown

🌐 Reachability 30/30
⚡ Speed 20/20
🔒 Security 5/15
🛠 Developer XP 12/20
✓ Reliability 7/15
Response Time 196ms

Fully tested on Apr 5, 2026

Technical Specifications

Auth No Auth
HTTPS NO
CORS NO
Category Science & Math
Difficulty Beginner
Verified: 2026-04-04

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