Covid Tracking Project vs NPPES

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

Uptime · 30d
Uptime · 90d100%100%
Uptime · 30d100%100%
P50 · ms237910
P95 · ms6122071
Authnonenone
CORSyesno
HTTPSyesyes
Card requirednono
Commercial useyesyes
Data licenseCC BY 4.0U.S. Government (public NPI data)
Free tierFree — no key required (archived dataset)Free — no key required
Rate limitUnpublishedUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

Covid Tracking Project vs NPPES: common questions

Which is more reliable, Covid Tracking Project or NPPES?

Both are neck-and-neck — Covid Tracking Project and NPPES each measure 100% uptime over 90 days on our probe schedule. Reliability here is verified from our own scheduled checks; use the 30-day bars above to see which has been steadier lately.

Which is faster, Covid Tracking Project or NPPES?

Covid Tracking Project has the lower median latency in our checks — Covid Tracking Project responds in 237 ms versus NPPES at 910 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 Covid Tracking Project and NPPES need an API key?

Neither needs a paid key — Covid Tracking Project is callable with no signup, and NPPES is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call Covid Tracking Project and NPPES from the browser?

Only Covid Tracking Project is browser-friendly — it returns CORS headers over HTTPS. NPPES needs a server-side call or proxy, so factor that into which one fits a front-end project.

Are Covid Tracking Project and NPPES free for commercial use?

Covid Tracking Project allows commercial use on its free tier, and NPPES allows commercial use on its free tier. 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.