Datamuse vs Open VSX Registry API

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

Uptime · 30d
Uptime · 90d92.2%100%
Uptime · 30d86.7%100%
P50 · ms180245
P95 · ms926693
Authnonenone
CORSnoyes
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedUnverified
Free tierFree — limits not publishedFree — limits not published
Rate limitUnpublished10800 req/window · 10799 remaining
In directory since2026-07-052026-07-05
operationalpartialdownno data

Datamuse vs Open VSX Registry API: common questions

Which is more reliable, Datamuse or Open VSX Registry API?

On our scheduled checks, Open VSX Registry API leads on measured uptime — Datamuse at 92.2% versus Open VSX Registry API at 100% 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, Datamuse or Open VSX Registry API?

Datamuse has the lower median latency in our checks — Datamuse responds in 180 ms versus Open VSX Registry API at 245 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 Datamuse and Open VSX Registry API need an API key?

Neither needs a paid key — Datamuse is callable with no signup, and Open VSX Registry API is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call Datamuse and Open VSX Registry API from the browser?

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

Are Datamuse and Open VSX Registry API free for commercial use?

Datamuse has unclear commercial terms, and Open VSX Registry API 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.