GitHub Contribution Chart Generator vs Open Library

Same instrument, two spec sheets — measured, not claimed.

Uptime · 30d
Uptime · 90d—%—%
Uptime · 30d—%—%
P50 · ms
P95 · ms
Authnonenone
CORSnoyes
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverified (derived from public GitHub profile data)Mixed — mostly open
Free tierFree — no keyUnlimited within courtesy limits
Rate limitUnpublishedSoft — identified UA appreciated
In directory since2026-07-052026-05-02
operationalpartialdownno data

GitHub Contribution Chart Generator vs Open Library: common questions

Which is more reliable, GitHub Contribution Chart Generator or Open Library?

On our scheduled checks, Open Library leads on measured uptime — GitHub Contribution Chart Generator at —% versus Open Library at —% over 90 days. These are our own probe results, not provider claims; the uptime bars above show the day-by-day record for both.

Do GitHub Contribution Chart Generator and Open Library need an API key?

Neither needs a paid key — GitHub Contribution Chart Generator is callable with no signup, and Open Library is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call GitHub Contribution Chart Generator and Open Library from the browser?

Only Open Library is browser-friendly — it returns CORS headers over HTTPS. GitHub Contribution Chart Generator needs a server-side call or proxy, so factor that into which one fits a front-end project.

Are GitHub Contribution Chart Generator and Open Library free for commercial use?

GitHub Contribution Chart Generator has unclear commercial terms, and Open Library has unclear commercial terms. We track service terms and the data license as separate fields — see the Commercial use and Data license rows above, and confirm both before shipping either in a paid product.