Numbers API

math · Data

Data No Auth Free & Open open_data

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](https://math.tools/api/numbers/)

Authentication

No authentication requiredFree to use with no key needed.

Sample Requests

GET GET /numbers/base

Convert a given number from one base to another base

https://api.apis.guru/v2/specs/math.tools/1.5/numbers/base?to=2024-12-31&from=2024-01-01&number=1

Hover any highlighted part to learn what it does

curl -X GET "https://api.apis.guru/v2/specs/math.tools/1.5/numbers/base?to=2024-12-31&from=2024-01-01&number=1"

import requests
params = {
    "to": "2024-12-31",
    "from": "2024-01-01",
    "number": "1"
}
response = requests.get(
    "https://api.apis.guru/v2/specs/math.tools/1.5/numbers/base",
    params=params,
)
print(response.json())

const url = new URL('https://api.apis.guru/v2/specs/math.tools/1.5/numbers/base');
url.searchParams.set('to', '2024-12-31');
url.searchParams.set('from', '2024-01-01');
url.searchParams.set('number', '1');

const response = await fetch(url); 
const data = await response.json();
console.log(data);

package main

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

func main() {
	baseURL, _ := url.Parse("https://api.apis.guru/v2/specs/math.tools/1.5/numbers/base")
	q := baseURL.Query()
	q.Set("to", "2024-12-31")
	q.Set("from", "2024-01-01")
	q.Set("number", "1")
	baseURL.RawQuery = q.Encode()
	targetURL := baseURL.String()
	req, _ := http.NewRequest("GET", targetURL, nil)

	client := &http.Client{}
	resp, _ := client.Do(req)
	defer resp.Body.Close()
	body, _ := io.ReadAll(resp.Body)
	fmt.Println(string(body))
}

require "net/http"
require "json"

uri = URI("https://api.apis.guru/v2/specs/math.tools/1.5/numbers/base")
uri.query = URI.encode_www_form({
  "to" => "2024-12-31",
  "from" => "2024-01-01",
  "number" => "1"
})

http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = uri.scheme == "https"

req = Net::HTTP::Get.new(uri)

res = http.request(req)
puts JSON.parse(res.body)

<?php
$url = "https://api.apis.guru/v2/specs/math.tools/1.5/numbers/base?" . http_build_query([
    "to" => "2024-12-31",
    "from" => "2024-01-01",
    "number" => "1"
]);
$opts = ["http" => [
    "method" => "GET",
]];
$ctx = stream_context_create($opts);
$res = file_get_contents($url, false, $ctx);
print_r(json_decode($res, true));

GET GET /numbers/cardinal

Get the cardinal of the given number

https://api.apis.guru/v2/specs/math.tools/1.5/numbers/cardinal?number=1&language=en

Hover any highlighted part to learn what it does

curl -X GET "https://api.apis.guru/v2/specs/math.tools/1.5/numbers/cardinal?number=1&language=en"

import requests
params = {
    "number": "1",
    "language": "en"
}
response = requests.get(
    "https://api.apis.guru/v2/specs/math.tools/1.5/numbers/cardinal",
    params=params,
)
print(response.json())

const url = new URL('https://api.apis.guru/v2/specs/math.tools/1.5/numbers/cardinal');
url.searchParams.set('number', '1');
url.searchParams.set('language', 'en');

const response = await fetch(url); 
const data = await response.json();
console.log(data);

package main

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

func main() {
	baseURL, _ := url.Parse("https://api.apis.guru/v2/specs/math.tools/1.5/numbers/cardinal")
	q := baseURL.Query()
	q.Set("number", "1")
	q.Set("language", "en")
	baseURL.RawQuery = q.Encode()
	targetURL := baseURL.String()
	req, _ := http.NewRequest("GET", targetURL, nil)

	client := &http.Client{}
	resp, _ := client.Do(req)
	defer resp.Body.Close()
	body, _ := io.ReadAll(resp.Body)
	fmt.Println(string(body))
}

require "net/http"
require "json"

uri = URI("https://api.apis.guru/v2/specs/math.tools/1.5/numbers/cardinal")
uri.query = URI.encode_www_form({
  "number" => "1",
  "language" => "en"
})

http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = uri.scheme == "https"

req = Net::HTTP::Get.new(uri)

res = http.request(req)
puts JSON.parse(res.body)

<?php
$url = "https://api.apis.guru/v2/specs/math.tools/1.5/numbers/cardinal?" . http_build_query([
    "number" => "1",
    "language" => "en"
]);
$opts = ["http" => [
    "method" => "GET",
]];
$ctx = stream_context_create($opts);
$res = file_get_contents($url, false, $ctx);
print_r(json_decode($res, true));

GET GET /numbers/currency

Spells out the number as a currency

https://api.apis.guru/v2/specs/math.tools/1.5/numbers/currency?number=1&language=en

Hover any highlighted part to learn what it does

curl -X GET "https://api.apis.guru/v2/specs/math.tools/1.5/numbers/currency?number=1&language=en"

import requests
params = {
    "number": "1",
    "language": "en"
}
response = requests.get(
    "https://api.apis.guru/v2/specs/math.tools/1.5/numbers/currency",
    params=params,
)
print(response.json())

const url = new URL('https://api.apis.guru/v2/specs/math.tools/1.5/numbers/currency');
url.searchParams.set('number', '1');
url.searchParams.set('language', 'en');

const response = await fetch(url); 
const data = await response.json();
console.log(data);

package main

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

func main() {
	baseURL, _ := url.Parse("https://api.apis.guru/v2/specs/math.tools/1.5/numbers/currency")
	q := baseURL.Query()
	q.Set("number", "1")
	q.Set("language", "en")
	baseURL.RawQuery = q.Encode()
	targetURL := baseURL.String()
	req, _ := http.NewRequest("GET", targetURL, nil)

	client := &http.Client{}
	resp, _ := client.Do(req)
	defer resp.Body.Close()
	body, _ := io.ReadAll(resp.Body)
	fmt.Println(string(body))
}

require "net/http"
require "json"

uri = URI("https://api.apis.guru/v2/specs/math.tools/1.5/numbers/currency")
uri.query = URI.encode_www_form({
  "number" => "1",
  "language" => "en"
})

http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = uri.scheme == "https"

req = Net::HTTP::Get.new(uri)

res = http.request(req)
puts JSON.parse(res.body)

<?php
$url = "https://api.apis.guru/v2/specs/math.tools/1.5/numbers/currency?" . http_build_query([
    "number" => "1",
    "language" => "en"
]);
$opts = ["http" => [
    "method" => "GET",
]];
$ctx = stream_context_create($opts);
$res = file_get_contents($url, false, $ctx);
print_r(json_decode($res, true));

Postman Setup Guide

Get Postman ↗

See official documentation for authentication and setup.

What can you build with Numbers API?

Numbers API is a Data API. Developers commonly use data APIs for:

enriching your app with third-party datasets
building data pipelines and ETL workflows
querying and searching large datasets
powering research, analysis, and reporting tools
syncing reference data into your own systems

No authentication required. This API is open — no signup or key needed. Ideal for quick prototypes and public-facing features. Numbers API is free to use, making it a low-risk choice to experiment with.

New to APIs? Read our beginner's guide · Learn about API keys · What is REST?

Open documentation ↗