10 Free API for Your Development Project

As a developer, when designing a website or an application, we sometimes need datasets conditioned on certain parameters (location, user data, etc.).

Instead of coding them ourselves and reinventing the wheel, there are ready-made and accessible solutions: public APIs!

Here, we will list the most useful public and free APIs (some up to a point) for development.

What is a Public API?

But before we list these most practical APIs, let's go back a bit.

API stands for Application Programming Interface.

Specifically, in the context of this article, an API is an entry point that we call to retrieve (or write) data. It therefore returns data that will be consumed by our site or app, often in JSON format (it can also be XML or any other format).

As we will see, the possible uses are numerous, and these APIs can greatly facilitate the development of a product.

Top 12 Free Public APIs

1 – OpenWeather Map

The name of this API is quite telling: OpenWeather Map is an interface that allows you to retrieve, from geographic data:

• The current weather;
• The weather forecast;
• The climatic forecast;
• The past weather.

• Link: https://openweathermap.org/api

• Limit: Free up to 60 calls/minute and 1 million calls per month

• Possible uses: Website listing historical weather during specific events; use for machine learning

2 – Open Food Fact

Open Food Fact is the reference API when we talk about data concerning food. Indeed, it's the dataset upon which the app Yuka is based!

It notably provides, for each food item in its database, information such as:

• The weight or quantity;
• The packaging;
• The nutri-score;
• The categories (snacks, drinks, etc.);
• The certifications (organic, plant-based, etc.);
• The countries of sale.

And many more elements!

• Link: https://fr.openfoodfacts.org/data

• Limit: No limit

• Possible uses: Food scanning app for allergens (like Bokha), list of possible food items to buy for a given recipe

3 – Trefle.io

Are you passionate about botany? There's a perfect API for you! trefle.io indeed allows, via queries, to retrieve a wealth of information about the plant world.

Want to retrieve all the red flowers? No problem. All plants that are between 5 and 20 cm tall? No problem.

• Link: https://docs.trefle.io/

• Limit: No limit

• Possible uses: App allowing you to find the ideal plant for your home

4 – Open Sky

This API allows you to retrieve, in real time, data from each aircraft flying around the globe. This data includes, for example, the location, the country of origin, and the velocity.

• Link: https://openskynetwork.github.io/opensky-api/

• Limit: No limit

• Possible uses: Create a personalized flight tracking app

Find tools to create or easily fetch API on Indie Dev Tools.

5 – TheMovieDB

The name of this API is quite clear: it is a movie database. It allows for multiple queries, for example:

• What movies are currently available in theaters?
• What were the best movies released in 2013?
• What is the best science fiction movie that Tom Cruise has acted in?

Depending on the queries, we will therefore retrieve elements with attributes (a movie will come for example with a title, a genre, the rating, whether it is intended for adults, etc.)

• Link: https://www.themoviedb.org/documentation/api

• Limit: No limit

• Possible uses: Create a smart search tool to find what movie to watch tonight

6 – RandomUser

RandomUser, as its name suggests, allows the generation of users (or rather human profiles), randomly.

As you can imagine, here we do not retrieve real data like with the other APIs, but we generate fake data. RandomUser can be particularly useful for creating stubs for your own APIs without needing to create user data yourself.

And RandomUser generates very complete profiles. We can notably retrieve the name, the gender, address, login coordinates (with encrypted password), etc.

• Link: https://randomuser.me/

• Limit: No limit

• Possible uses: Fill your database with fake users for your tests

7 – CountryLayer

This API is well known and already widely used. It allows you to retrieve a lot of data about countries around the world.

Through this API, we retrieve:

• The country code;
• The capital;
• The coordinates;
• The languages.

And many other data.

• Link: http://countrylayer.com/

• Limit: 100 searches per month with limited returned data, payable beyond that

• Possible uses: Display countries in a selectbox, create an interactive map with information display on click

8 – Zippopotam

Still in the same theme of geography, here is another very handy API: Zippopotam!

This API allows, from a country code and a postal code, to retrieve all the information of a city.

For example, the URL https://api.zippopotam.us/fr/33000 will return information about the city of Bordeaux, France (name, geographical coordinates, and region).

• Link: http://www.zippopotam.us/

• Limit: No limit

• Possible uses: Retrieve city information from its postal code to avoid forcing the user to manually fill in all the information

9 – Giphy

Do we need to introduce Giphy? This giant dictionary of gifs allows, via an SDK and APIs, to retrieve gifs according to several criteria (trending, via search, random, etc.).

• Link: https://developers.giphy.com/

• Limit: No limit

• Possible uses: Create a tool for generating and sending random gifs

10 – Cloud Convert

Cloud Convert is a set of APIs that allow multiple actions on files:

• Conversion (e.g., docx to pdf);
• File optimization (image or pdf compression);
• Merging files (merging 2 pdfs);
• Creating archives.

Very handy when you need to manipulate files.

• Link: https://cloudconvert.com/api/v2

• Limit: 25 conversions per day, payable beyond that

• Possible uses: Automatically convert files sent via a form into pdf if those provided are not in this format.

List of Free and Paid APIs

If you haven't found what you're looking for in our list, don't panic, there may still be an API that meets your needs!

There is a site that lists a large part of the APIs available on the web. However, be aware, some are paid from the start.

The site is called RapidAPI.

And, if you're interested, you can also create and make available (or even sell) your APIs on this site!