API Discovery Dashboard
A curated list of free and popular public APIs for your next project.
What Is an API, and Why Should You Care?
An API (Application Programming Interface) is a defined way for one piece of software to request data or trigger an action from another, without needing to know how that other system works internally. Think of it like a restaurant menu — you don't need to know how the kitchen works, you just order off the menu and get a predictable result back.
For Web Developers
- ▸Pull in data you don't own or generate yourself — weather, maps, exchange rates — instead of building it from scratch.
- ▸Handle payments, authentication, and email through trusted third-party services (Stripe, Auth0, SendGrid) rather than reinventing them.
- ▸Connect a frontend to a backend — most modern web apps are really just a UI calling APIs behind the scenes.
For Sysadmins & IT
- ▸Automate cloud infrastructure through provider APIs (AWS, Azure, GCP) instead of clicking through a console every time.
- ▸Pull metrics into monitoring tools, or push alerts out to Slack/Teams/PagerDuty via webhooks.
- ▸Script routine tasks against ticketing systems (Jira, ServiceNow) or directory services instead of doing them by hand.
Quick vocabulary: an endpoint is a specific URL you send a request to; most modern APIs return data as JSON; an API key authenticates who's calling; and a rate limit caps how many requests you can make in a given time.
Browse the API Directory
Search or filter the list below to find one that fits your project.
| API Name | Category | Link |
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Frequently Asked Questions
Quick answers to common questions about finding and using public APIs.
Are public APIs actually free to use?
Most public APIs offer a free tier, but "free" usually comes with limits — a capped number of requests per day or per month, lower rate limits than paid tiers, or fewer data fields returned. Always check the provider's own pricing page before building something you depend on; free tiers can change or shrink over time.
Do I need an API key for every API?
No. Some APIs, like IPify, work with zero authentication for basic use. Most others require a free API key you register for, which is used to track your usage against rate limits rather than to charge you directly.
What's a good free weather API?
OpenWeatherMap is the most commonly used option, with a generous free tier covering current conditions and forecasts for any location worldwide. Meteoblue is a good alternative when you need higher-precision or agricultural-grade forecast data.
How do I find my server or client's public IP address programmatically?
IPify returns your current public IP address in plain JSON with a single request and no API key required — it's the simplest option for this specific task.
What's a rate limit, and what happens if I hit it?
A rate limit caps how many requests you can send in a given time window — for example, 60 requests per minute. Exceeding it typically returns an HTTP 429 "Too Many Requests" response rather than an error in your data. Well-behaved API clients check for this response and slow down automatically rather than retrying immediately.
Is there an API that lists other APIs?
Yes — Public APIs (Meta) does exactly this: it returns a categorized, filterable list of other public APIs, which is useful for discovering new tools and services to integrate into a project. It's part of the inspiration for this page.
What's the difference between REST and other API styles I might see?
REST is by far the most common style for public APIs, using standard HTTP methods (GET, POST, etc.) and typically returning JSON. You'll occasionally see GraphQL APIs, which let the client specify exactly which fields it wants in a single request instead of hitting multiple fixed endpoints. Nearly every API listed on this page is REST-based.