Best Open Source Projects APIs in 2026

The top 11 of 11 free Open Source Projects APIs, ranked by how easy they are to start with (API key, HTTPS, CORS), how reliable they are in our daily health checks, and what developers rate them. GitHub Contribution Chart Generator API takes the top spot.

Last tested Oct 24, 2026 · Rankings update daily

1
GitHub Contribution Chart Generator API
Online · 657 ms
Create an image of your GitHub contributions.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
2
GitHub ReadMe Stats API
Online · 729 ms
Add dynamically generated statistics to your GitHub profile ReadMe.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
3
Metabase API
Online · 650 ms
An open source Business Intelligence server to share data and analytics inside your company.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
4E
Evil Insult Generator API
Online · 1098 ms
Evil Insults. A free open source projects API by Evil Insult Generator.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
5
Neuronto ARD Registry API
Online · 766 ms
Search index of MCP servers, agents and APIs, with the tools each server actually exposes.
- No API key needed
- Callable from the browser (CORS)
- HTTPS
No authHTTPSCORS
6
Drupal.org API
Online · 77 ms
Drupal.org. A free open source projects API by drupal.org.
- No API key needed
- Fast: 77 ms response
- HTTPS
No authHTTPSCORS ?
7
Shields API
Online · 791 ms
Concise, consistent, and legible badges in SVG and raster format.
- No API key needed
- HTTPS
No authHTTPSCORS ?
8D
Datamuse API
Online · 810 ms
Word-finding query engine. A free open source projects API by Datamuse API.
- No API key needed
- HTTPS
No authHTTPSCORS ?
9
Libraries.io API
Online · 2099 ms
Metadata, dependencies and release history for open-source packages across 30+ managers.
- Callable from the browser (CORS)
- HTTPS
apiKeyHTTPSCORS
10
Creative Commons Catalog API
Online · 3612 ms
Search among openly licensed and public domain works.
- Callable from the browser (CORS)
- HTTPS
OAuthHTTPSCORS
11
Countly API
Online · 403 ms
Comprehensive API reference for Countly Enterprise.
- No API key needed
No authNo HTTPSCORS ?

Open Source Projects APIs compared

Top Open Source Projects APIs compared
API	API key	HTTPS	CORS	Uptime	Response	Rating
GitHub Contribution Chart Generator	No	Yes	Yes	Up	657 ms	Not rated
GitHub ReadMe Stats	No	Yes	Yes	Up	729 ms	Not rated
Metabase	No	Yes	Yes	Up	650 ms	Not rated
Evil Insult Generator	No	Yes	Yes	Up	1098 ms	Not rated
Neuronto ARD Registry	No	Yes	Yes	Up	766 ms	Not rated
Drupal.org	No	Yes	Unknown	Up	77 ms	Not rated
Shields	No	Yes	Unknown	Up	791 ms	Not rated
Datamuse	No	Yes	Unknown	Up	810 ms	Not rated
Libraries.io	Required	Yes	Yes	Up	2099 ms	Not rated
Creative Commons Catalog	OAuth	Yes	Yes	Up	3612 ms	Not rated

More Open Source Projects APIs

Best Open Source Projects API FAQ

What is the best free Open Source Projects API in 2026?

Based on access, reliability and developer ratings, the top free Open Source Projects APIs right now are GitHub Contribution Chart Generator API, GitHub ReadMe Stats API and Metabase API. GitHub Contribution Chart Generator API ranks first. Rankings update daily from health checks of all 11 Open Source Projects APIs in the directory.

What is the best Open Source Projects API without an API key?

GitHub Contribution Chart Generator API, GitHub ReadMe Stats API and Metabase API need no API key, so you can call them without signing up. 9 of the 11 ranked Open Source Projects APIs are keyless.

Which Open Source Projects API works from the browser?

GitHub Contribution Chart Generator API, GitHub ReadMe Stats API and Metabase API support CORS over HTTPS, so front-end JavaScript can call them directly without a proxy.

How are these APIs ranked?

Each API gets a score from: no API key (+), HTTPS (+), CORS support (+), 30-day uptime and response time from our daily health checks, and ratings from developers on this site. APIs that failed three checks in a row are left out until they recover.