Launch Library 2 vs Open Notify

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

Uptime · 30d
Uptime · 90d3.9%71.6%
Uptime · 30d1.7%65.0%
P50 · ms546241
P95 · ms10104298
Authnonenone
CORSyesyes
HTTPSyesno
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedn/a
Free tierFree — no key (The Space Devs LL2)Unlimited (volunteer-run)
Rate limitAnonymous requests are throttled to a low rate (see docs)Please be gentle
In directory since2026-07-052026-05-02
operationalpartialdownno data

Launch Library 2 vs Open Notify: common questions

Which is more reliable, Launch Library 2 or Open Notify?

On our scheduled checks, Open Notify leads on measured uptime — Launch Library 2 at 3.9% versus Open Notify at 71.6% over 90 days. These are our own probe results, not provider claims; the uptime bars above show the day-by-day record for both.

Which is faster, Launch Library 2 or Open Notify?

Open Notify has the lower median latency in our checks — Launch Library 2 responds in 546 ms versus Open Notify at 241 ms (P50). Tail latency (P95) is in the table above; for most workloads the median is the number that shapes how the API feels.

Do Launch Library 2 and Open Notify need an API key?

Neither needs a paid key — Launch Library 2 is callable with no signup, and Open Notify is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call Launch Library 2 and Open Notify from the browser?

Only Launch Library 2 is browser-friendly — it returns CORS headers over HTTPS. Open Notify needs a server-side call or proxy, so factor that into which one fits a front-end project.

Are Launch Library 2 and Open Notify free for commercial use?

Launch Library 2 has unclear commercial terms, and Open Notify 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.