Which free APIs are best for news, knowledge, and language?
For general news, The Guardian's free developer key gives you full articles going back decades. Spaceflight News covers space news with no key, Wikipedia gives you a summary of almost anything, Datamuse finds rhymes and related words, and LibreTranslate handles translation if you run it yourself. These are the building blocks for readers, study tools, and writing apps.
12. The Guardian
News · Free developer key
The Guardian Open Platform gives you search across The Guardian's articles, with headlines, sections, tags, and full text. The free developer key is for non-commercial use, which makes it great for personal projects and learning.
Build ideas:
- Beginner: a page with today's top headlines in one section, like technology.
- Weekend: a topic tracker that shows how often a subject appeared in the news over time.
- Product prototype: a daily briefing that summarizes the top stories in your interests with an AI model (check their terms before going commercial).
Claude Code prompt:
Read https://open-platform.theguardian.com/documentation/.
Build a "daily briefing" page that pulls the 10 latest technology articles and
shows each headline with a two-sentence summary. Call the API from a server
route with the key in an environment variable and cache for 1 hour.
13. Spaceflight News
News · No key
The Spaceflight News API collects space news articles, blog posts, and reports from dozens of sites, with links to the launches and events they cover. It has more than 36,000 articles.
Build ideas:
- Beginner: a space news feed.
- Weekend: a launch tracker that shows news for upcoming launches.
- Product: a weekly space newsletter that is mostly assembled for you.
Claude Code prompt:
Read https://api.spaceflightnewsapi.net/v4/docs/.
Build a space news page with the latest 20 articles as cards with images,
a search box, and a filter by news site. Cache for 15 minutes.
14. Wikipedia
Knowledge · No key
The Wikipedia API gives you article summaries, images, search, and "on this day" events, in hundreds of languages. The simplest part is the page summary endpoint, which returns a short description and a thumbnail for any topic. Send a User-Agent that identifies your app.
Build ideas:
- Beginner: an "on this day in history" page.
- Weekend: a hover preview for any word or name on your blog that shows a Wikipedia summary.
- Product: a study tool that turns any article into flashcards with an AI model.
Claude Code prompt:
Read https://en.wikipedia.org/api/rest_v1/.
Build an "on this day" page that shows 5 historical events for today's date,
each with a summary and image from the page summary endpoint.
Send a descriptive User-Agent and cache for 24 hours.
15. Datamuse
Words · No key · Up to 100,000 requests a day
Datamuse is a word-finding engine. Ask for words that rhyme, mean something similar, sound alike, or are often used together. It is a hidden gem for anyone building writing tools.
Build ideas:
- Beginner: a rhyme finder.
- Weekend: a "find a better word" tool that suggests stronger alternatives as you write.
- Product: a naming tool that suggests brand or domain names from a few keywords.
Claude Code prompt:
Read https://www.datamuse.com/api/.
Build a naming tool: I enter 2 or 3 keywords and get name ideas from related
words, rhymes, and combinations, with a button to check if the .com looks taken.
16. LibreTranslate
Translation · Open source; self-host free, or use the hosted service with a paid key
LibreTranslate is open-source machine translation you can run on your own server for free. The public instance at libretranslate.com now requires a paid key, so the free route is to run it yourself, for example with Docker.
Build ideas:
- Beginner: a simple two-box translator.
- Weekend: a language practice app that shows a sentence in your target language and checks your translation.
- Product: a translation layer for user comments or support tickets, without sending data to a big tech company.
Claude Code prompt:
Read https://github.com/LibreTranslate/LibreTranslate.
Set up LibreTranslate locally with Docker, then build a page with two text
boxes and a language picker that translates as I type (debounced), calling
my local instance.
Which free APIs are best for entertainment and games?
For entertainment apps, TVMaze covers TV shows with no key, RAWG covers video games with a free key, Open Library covers books, and Open Trivia DB, PokéAPI, and Deck of Cards are perfect for games. These are the most fun APIs on the list and the best ones to learn with, because the results are easy to see.
17. TVMaze
TV · No key
TVMaze has TV shows, episodes, cast, schedules, and images. It is free, needs no key, and allows about 20 calls every 10 seconds. The data is shared under a Creative Commons license, so credit TVMaze in your app.
Build ideas:
- Beginner: a show search with posters and summaries.
- Weekend: a "what's on tonight" page from the daily TV schedule.
- Product: a watch tracker that tells you when new episodes of your shows air.
Claude Code prompt:
Read https://www.tvmaze.com/api.
Build a watch tracker: I search for shows and add them to my list, and the home
page shows the next episode date for each one. Save my list in local storage
and credit TVMaze in the footer.
18. RAWG
Video games · Free key · Attribution required
RAWG is one of the largest video game databases, with release dates, platforms, ratings, screenshots, and stores. The free key requires you to credit RAWG with a link.
Build ideas:
- Beginner: a game search with cover art.
- Weekend: a "what should I play next?" picker based on genres and platforms you own.
- Product: a backlog tracker for gamers with release reminders.
Claude Code prompt:
Read https://rawg.io/apidocs.
Build a "what should I play next?" page: I pick platforms and genres and get
5 highly rated games with screenshots. Call the API from a server route with
the key in an environment variable, and add the required RAWG credit link.
19. Open Library
Books · No key
Open Library, from the Internet Archive, has data on millions of books: titles, authors, editions, subjects, and cover images. Search by title, author, or ISBN.
Build ideas:
- Beginner: a book search with covers.
- Weekend: a reading tracker with a shelf of books you have read.
- Product: a book club app that suggests the next book and tracks everyone's progress.
Claude Code prompt:
Read https://openlibrary.org/developers/api.
Build a reading tracker: search books, add them to "want to read", "reading",
or "read" shelves with covers, and show how many books I read this year.
20. Open Trivia DB
Games · No key · Attribution required
Open Trivia DB is a free database of thousands of trivia questions across categories and difficulty levels, shared under a Creative Commons license. The docs page builds your request URL for you.
Build ideas:
- Beginner: a 10-question quiz.
- Weekend: a multiplayer trivia night where friends join from their phones.
- Product: a team-building quiz tool for remote meetings.
Claude Code prompt:
Read https://opentdb.com/api_config.php.
Build a 10-question quiz with a category picker, a timer per question, and a
final score screen. Decode the HTML entities in the questions and credit
Open Trivia DB.
21. PokéAPI
Games · No key
PokéAPI has data on every Pokémon: stats, types, moves, evolutions, and sprites. It is the most popular "first API" for learning, because it is free, fast, and fun. They ask you to cache results to keep it free for everyone.
Build ideas:
- Beginner: a Pokédex with search and sprites.
- Weekend: a team builder that shows type strengths and weaknesses.
- Product: a learning app that uses Pokémon stats to teach kids charts and math.
Claude Code prompt:
Read https://pokeapi.co/docs/v2.
Build a team builder: pick up to 6 Pokémon, see their sprites and stats, and a
chart of which types the team is weak against. Cache every response.
22. Deck of Cards
Games · No key
The Deck of Cards API shuffles and deals a virtual deck for you, with card images, and remembers the deck between requests. It takes care of the boring parts of any card game.
Build ideas:
- Beginner: a "draw a card" page.
- Weekend: a simple blackjack game against the computer.
- Product: a multiplayer card game room where friends play over the web.
Claude Code prompt:
Read https://deckofcardsapi.com/.
Build a blackjack game against the dealer using a new shuffled deck each round,
with card images, hit and stand buttons, and a running win/loss count.
Which free APIs are best for images and developer tools?
NASA's API gives you free space images and data, Unsplash gives you high-quality photos with a free key, and the GitHub API lets you build tools around code, issues, and developer profiles. Each needs or benefits from a free key, and each comes with simple rules: use a real key for production, credit photographers, and stay within rate limits.
23. NASA
Space · Free key (DEMO_KEY for testing)
The NASA API includes the Astronomy Picture of the Day, near-Earth asteroids, Mars rover photos, and Earth imagery. You can test with DEMO_KEY, which allows 30 requests an hour, and a free personal key raises that to 1,000 an hour.
Build ideas:
- Beginner: an Astronomy Picture of the Day page.
- Weekend: a "space on your birthday" page that shows the picture of the day from any date.
- Product: a daily space wallpaper app.
Claude Code prompt:
Read https://api.nasa.gov/.
Build a "space on your birthday" page: pick a date and see the Astronomy
Picture of the Day for it, with the title and explanation. Use my key from an
environment variable on the server and cache each date forever.
24. Unsplash
Photos · Free key · Credit the photographer
Unsplash gives you search across millions of free high-quality photos. A new app starts in demo mode with 50 requests an hour, and you can apply for more. The rules are simple: credit the photographer and link to Unsplash.
Build ideas:
- Beginner: a random photo background for your homepage.
- Weekend: a mood board maker that pulls photos for a keyword.
- Product: an image picker inside your own CMS or newsletter tool.
Claude Code prompt:
Read https://unsplash.com/documentation.
Build a mood board page: I type a keyword and get a grid of 12 photos, can pin
favorites, and each photo shows the photographer's name and link as Unsplash
requires. Call the API from a server route with the key in an environment variable.
25. GitHub
Developer tools · No key for light use, free token for more
The GitHub API gives you repositories, issues, pull requests, users, and stars. Without a token you get 60 requests an hour, and a free personal token raises that to 5,000 an hour. It is the backbone of most developer tools.
Build ideas:
- Beginner: a profile card that shows your top repositories and stars.
- Weekend: a dashboard of open issues across all your projects.
- Product: a "good first issue" finder for new contributors in a language they choose.
Claude Code prompt:
Read https://docs.github.com/en/rest.
Build a dashboard that lists open issues across all my public repositories,
grouped by repo and sorted by age. Use a personal access token from an
environment variable on the server and cache for 10 minutes.
What can you build by combining these APIs?
The most interesting projects combine two to four APIs, because each one adds a layer of data the others do not have. A road trip planner, a travel prep tool, or a smart morning briefing all come from stacking free APIs from this list. Claude Code handles combinations well if you name every API in the prompt.
A few combinations worth building:
- Road trip planner: Nominatim for the stops, Open Charge Map for chargers along the way, Open-Meteo for weather at each stop, and Nager.Date to warn about holiday traffic.
- Travel prep page: REST Countries for currency, language, and time zone, Frankfurter for the exchange rate, Nager.Date for holidays during your trip, and Open-Meteo for the forecast.
- Morning briefing: Open-Meteo for your weather, The Guardian for headlines, CoinGecko or Alpha Vantage for your watchlist, and NASA's picture of the day as the header.
- Kids' learning app: PokéAPI for stats to practice math, Open Trivia DB for quizzes, and Wikipedia for "learn more" summaries.
- Smart grocery list: TheMealDB for the week's recipes, Open Food Facts to check nutrition and allergens, and Frankfurter if you shop across borders.
Can you build a paid product on free APIs?
Sometimes. Some APIs on this list, like Open-Meteo and The Guardian, are free only for non-commercial use, and others, like Alpha Vantage, have free limits too low for real traffic. Before charging money, read each API's terms, budget for a paid plan, cache aggressively, and have a backup source for anything critical.
The short videos promise that people turn these into "full platforms with real paying users." It can happen, but here is what that path actually looks like:
- Read the terms. "Free" often means free for personal or non-commercial use. Commercial use may need a paid plan or written permission.
- Credit where required. TVMaze, RAWG, Open Trivia DB, and Unsplash all require attribution. It takes one line of text.
- Cache everything you can. It keeps you under rate limits, makes your app faster, and protects you when the API has a bad day.
- Keep keys on the server. A key in browser code can be copied and used up by someone else.
- Plan for the API to change or disappear. REST Countries changed its rules overnight. Keep your API calls in one place in your code so you can swap the source quickly.
- Use free APIs to validate, then pay to scale. A free API is a great way to test whether anyone wants your idea. If people pay, a paid data plan is a small cost.
What are the MCP servers in public-apis?
The newer "MCP Servers" section of public-apis lists APIs that AI agents like Claude can use directly as tools, through the Model Context Protocol. Instead of writing code that calls an API, you install the server into Claude, Cursor, or VS Code, and the agent calls it for you while it works.
The section is small so far, with nine entries, including GitHub's official MCP server and the Filesystem server from the MCP project. It is worth watching. As more APIs ship MCP servers, "paste the docs into Claude Code" turns into "give Claude the tool and ask the question."
Frequently Asked Questions
Are the APIs in public-apis really free?
Most have a free option. 969 of the 2,029 APIs need no key, and 899 need a free key. "Free" often comes with rate limits or a non-commercial-use rule, so read each API's terms before you build something you plan to sell.
Which free API is best for beginners?
PokéAPI is the most popular first API: it needs no key, responds quickly, and the results are easy to check. Open-Meteo and Open Trivia DB are also great starters, because their docs pages build the request URL for you.
Do I need to know how to code to use these APIs?
Not much anymore. With an AI coding tool like Claude Code, you can describe what you want and give it the API's docs link, and it writes the code. Knowing the basics still helps you test the result, keep keys safe, and fix problems.
Why do some APIs in the list not work?
The list is maintained by volunteers, and APIs change or shut down over time. In my October 2026 check, about 11% of the documentation links were dead. Always make one test request before building on an API.
Where should I store an API key?
On the server, in an environment variable, never in code that runs in the browser. Ask Claude Code to create a server route that calls the API, so the key never reaches the visitor's browser.
