M
API Matrix

Numbers API

Science & Math / API Key Intermediate HTTPS
Varies by plan (check documentation)
74 Score
Grade B
Visit Official Site Compare Alternatives

Overview

The Numbers API from math.tools provides facts, trivia, and mathematical data about numbers — including the number of the day, random numbers, and detailed number properties. An API key is required and you include it as a header in each request. It is a fun API for adding interesting number facts to educational apps, games, or daily fact features.

💡

Beginner Tip

Include your API key as the "X-Api-Key" header rather than a query parameter for better security, and always check the "error" field in the response before trying to use the "result" field.

Available Data

randomly generated data
customizable output format
Numbers data via REST API
JSON-formatted response data
Requires API key authentication

Example Response

JSON Response 
{
  "status": "success",
  "data": {
    "result": "Data from Numbers",
    "description": "Number of the day, random number, number facts and anything else you want to do with numbers",
    "timestamp": "2025-01-15T10:00:00Z"
  }
}

Field Reference

result Contains the main data about the number, including facts, properties, and classifications.
error True if the request encountered an error; false when the response is successful.
message A human-readable error description when the error field is true.
number The number you queried, echoed back in the response for confirmation.
fact An interesting fact or piece of trivia about the requested number.

Implementation Example 

const url = "https://math.tools/api/numbers/";
// Replace headers or query params with the values required by this API.
const response = await fetch(url, {
  headers: {
  "X-API-Key": "YOUR_API_KEY"
  }
});
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

401 Unauthorized The API key is missing, incorrect, or has expired.
✓ Sign up at https://math.tools to get your API key and include it in the X-Api-Key request header.
429 Too Many Requests You have exceeded your plan rate limit for the billing period.
✓ Check your usage dashboard on math.tools and consider upgrading your plan or adding request throttling to your code.
"error" field in response An invalid number or unsupported operation was requested.
✓ Ensure the number is within a valid range (try integers first) and check the API docs for supported number types.

Matrix Score Breakdown

🌐 Reachability 30/30
⚡ Speed 10/20
🔒 Security 15/15
🛠 Developer XP 9/20
✓ Reliability 10/15

Partially tested on Apr 5, 2026

Technical Specifications

Auth API Key
HTTPS REQUIRED
CORS NO
Category Science & Math
Difficulty Intermediate
Verified: 2026-04-04

Similar APIs

View All →

CORE

72

CORE provides access to millions of open-access research papers from repositories and journals worldwide.

API Key Intermediate HTTPS

Materials Platform for Data Science

69

The Materials Platform for Data Science (MPDS) API provides access to curated experimental data about materials — things like crystal structures, physical properties, and phase diagrams.

API Key Intermediate HTTPS

arcsecond.io

⭐ Beginner's Pick
82

arcsecond.io is a free astronomy API that aggregates data from multiple space databases, including stars, planets, exoplanets, and observing sites.

No Auth Beginner HTTPS 226ms

arXiv

0

arXiv provides programmatic access to curated research-sharing platform: physics, mathematics, quantitative finance, and economics via REST API.

No Auth Beginner HTTPS 71ms

GBIF

⭐ Beginner's Pick
52

GBIF (Global Biodiversity Information Facility) is a free, open API providing access to hundreds of millions of species occurrence records from around the world.

No Auth Beginner HTTPS 955ms