freeapis

Numbers

Number of the day, random number, number facts and anything else you want to do with numbers

Authentication
API Key
HTTPS
Yes
CORS
No

Overview

Numbers (math.tools) provides number data — key-based (the API responds even without a valid key, verified).

Quick Start

Number of the day (replace YOUR_KEY):

curl "https://api.math.tools/numbers/nod?key=YOUR_KEY"
{ "success": { "total": 1 }, "copyright": { "copyright": "2019-21 https://math.tools" }, "contents": { "nod": { "category": { "name": "number" } } } }

Authentication

  • Register at math.tools → API key.
  • Send it as the key query parameter.

Rate Limits & Notes

  • Free tier with limits (check the docs); paid plans scale.
  • Number facts.

FAQ

Is Numbers free? Free tier with limits; more is paid.

Does it work without a key? It responds with data even with an invalid key (verified) — but use a real key for reliable access.

What’s the auth style? key query parameter.

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