Using the Population.io Public API in JavaScript

The Population.io Public API provides access to population data for a variety of countries and age ranges. In this blog post, we’ll walk through how to use the API in JavaScript.

Getting an API Key

Before we start making API calls, we need to get an API key. Here are the steps to follow:

  1. Go to the Population.io API website.
  2. Click on “Get started for free” and sign up for an account.
  3. Once you have an account, go to the dashboard and click on “API keys”.
  4. Click on “New API key” to generate a new key.

Make sure to keep your API key secure, as it provides access to your data.

Making API Requests

To make an API request, we’ll first need to construct the URL we want to call. Here’s the general format for the URL:

  • {endpoint}: The type of data you want to retrieve (e.g. population, life-expectancy).
  • {value}: The country or region you want to retrieve data for (e.g. United States, Europe).
  • {property}: The specific property you want to retrieve data for (e.g. female, male, total).
  • {date}: The year you want to retrieve data for (e.g. 2021).

Here’s an example URL to retrieve the total population for the United States in 2021:


To make an API call in JavaScript, we’ll use the fetch function. Here’s an example function that makes an API request and logs the result to the console:

async function fetchData(endpoint, value, property, date, apiKey) {
  const url = `https://api.population.io/1.0/${endpoint}/${value}/${property}/${date}.json?api_key=${apiKey}`;
  const response = await fetch(url);
  const data = await response.json();

To use this function, simply call it with the relevant parameters:

fetchData('population', 'United States', 'total', '2021', 'YOUR_API_KEY');

Example API Requests

Here are some example API requests for different types of data:

Total population by country and year

Retrieve the total population for the United States in 2021:

fetchData('population', 'United States', 'total', '2021', 'YOUR_API_KEY');

Life expectancy by country, gender, and year

Retrieve the life expectancy for females in Canada in 2021:

fetchData('life-expectancy', 'Canada', 'female', '2021', 'YOUR_API_KEY');

Age distribution by country and year

Retrieve the age distribution for Japan in 2021:

fetchData('age-distribution', 'Japan', 'total', '2021', 'YOUR_API_KEY');


In this blog post, we’ve walked through how to use the Population.io Public API in JavaScript. By making API requests, we can retrieve a variety of population data for different countries and age ranges. With this information, we can build applications that help us better understand demographic trends and make data-driven decisions.