Tired of building todo apps? These APIs give you real data to build something interesting.

1. Open Meteo — Weather without an API key

No signup, no API key, no rate limit worries. Just call it.

curl "https://api.open-meteo.com/v1/forecast?latitude=50.85&longitude=4.35&current_weather=true"

Returns temperature, wind speed, weather code. Supports hourly and daily forecasts for any location on Earth.

Build with it:

• CLI weather tool (weather brussels → current conditions)
• Weather widget for your portfolio site
• Historical weather comparison tool

2. PokeAPI — 1,000+ Pokémon with full data

Every Pokémon, every move, every ability, every generation. Completely free.

curl "https://pokeapi.co/api/v2/pokemon/pikachu"

Build with it:

• Pokédex app (classic portfolio project, but with real data)
• Pokémon team builder with type effectiveness calculations
• “Who’s That Pokémon?” guessing game

3. JSONPlaceholder — Fake REST API for prototyping

100 posts, 500 comments, 200 todos, 10 users. Supports GET, POST, PUT, DELETE (writes are faked but return proper responses).

curl "https://jsonplaceholder.typicode.com/posts/1"

Build with it:

• Practice building a full CRUD frontend without a backend
• Test your API client library
• Prototype a dashboard UI with realistic data

4. restcountries.com — Data on every country

Population, languages, currencies, borders, flags, timezones for all 250 countries.

curl "https://restcountries.com/v3.1/name/belgium"

Build with it:

• Country comparison tool
• “Guess the flag” game
• Travel planning app with timezone calculations

5. NASA APOD — Astronomy Picture of the Day

NASA publishes a stunning space photo every day with an explanation. Free API key (instant, just provide email).

curl "https://api.nasa.gov/planetary/apod?api_key=DEMO_KEY"

Build with it:

• Daily space wallpaper app
• Astronomy photo gallery with search
• Desktop widget that shows today’s space photo

Bonus: APIs that are almost free

• GitHub API — 5,000 requests/hour with a token. Build repo analytics, contribution trackers.
• OpenLibrary API — Book data for millions of titles. No key needed.
• The Dog API / Cat API — Random animal photos. Perfect for placeholder content.

The portfolio trick

Instead of building another todo app, build something with a real API. “I built a weather CLI tool” is more interesting in an interview than “I built a todo app.” It shows you can work with external data, handle errors, and parse real-world responses.

Pick an API, build something this weekend, deploy it, add it to your portfolio.

Getting started checklist

1. Pick one API from this list that interests you
2. Read the docs for 10 minutes — just the authentication and one endpoint
3. Make your first request with curl or your browser
4. Build the simplest possible thing that uses the data (a single page that displays something)
5. Deploy it (Vercel, Netlify, or GitHub Pages — all free)
6. Add it to your GitHub profile README

The whole process takes 2-4 hours. You’ll learn more about working with APIs than any tutorial could teach you.

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