# Numbers API

**Provider:** Numbers
**Category:** maps
**Base URL:** `https://api.math.tools`
**Auth:** api-key — `X-Mathtools-Api-Secret: YOUR_API_KEY`
**Rate Limit:** Not officially published
**Free Tier:** Yes — available
**Pricing:** Enterprise / contact sales (subscription)
**Docs:** https://api.math.tools

## Description

All about Numbers. REST access with json/xml/jsonp result support. Below is the documentation for the Numbers API. You can try them out right here. Find more information and subscribe at math.tools

## Endpoints

| Method | Endpoint | Description |
|--------|----------|-------------|
| GET | `https://api.math.tools/numbers/base` | Convert a given number from one base to another base |
| GET | `https://api.math.tools/numbers/base/binary` | Convert a given number to binary |
| GET | `https://api.math.tools/numbers/base/hex` | Convert a given number to hexadecimal |
| GET | `https://api.math.tools/numbers/base/octal` | Convert a given number to octal |
| GET | `https://api.math.tools/numbers/cardinal` | Get the cardinal of the given number |
| GET | `https://api.math.tools/numbers/currency` | Spells out the number as a currency |
| GET | `https://api.math.tools/numbers/fact` | Get a random fact about a number |
| GET | `https://api.math.tools/numbers/is-cube` | Checks whether a given number is a cube number or not. |

## Authentication

API key in the request header (X-Mathtools-Api-Secret)

```
X-Mathtools-Api-Secret: YOUR_API_KEY
```

## Sample Request

```bash
curl -X GET 'https://api.math.tools/numbers/base' \
  -H 'X-Mathtools-Api-Secret: YOUR_API_KEY'
```

## Sample Response

```json
{}
```

## Pricing Details

Free and open. Number facts API (numbersapi.com); no paid tiers.

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*Source: [API Map](https://apimap.dev/apis/numbers/) — CC BY 4.0*