EPA vs ONS

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

Uptime · 30d
Uptime · 90d54.9%100%
Uptime · 30d66.7%100%
P50 · ms3150732
P95 · ms49661819
Authnonenone
CORSyesyes
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedUnverified
Free tierFree — limits not publishedFree — limits not published
Rate limitUnpublishedUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

EPA vs ONS: common questions

Which is more reliable, EPA or ONS?

On our scheduled checks, ONS leads on measured uptime — EPA at 54.9% versus ONS 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, EPA or ONS?

ONS has the lower median latency in our checks — EPA responds in 3150 ms versus ONS at 732 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 EPA and ONS need an API key?

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

Can I call EPA and ONS from the browser?

Yes — both EPA and ONS send CORS headers over HTTPS, so front-end code can fetch either directly with no backend proxy. That makes them easy to swap in a client-side app while you compare responses.

Are EPA and ONS free for commercial use?

EPA has unclear commercial terms, and ONS 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.