Free Public APIs API vs WhoisXML API Email Verification API

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

Uptime · 30d
Uptime · 90d—%—%
Uptime · 30d—%—%
P50 · ms
P95 · ms
AuthnoneapiKey
CORSyesyes
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedUnverified
Free tierFree — limits not publishedFree tier — API key required
Rate limitUnpublishedUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

Free Public APIs API vs WhoisXML API Email Verification API: common questions

Which is more reliable, Free Public APIs API or WhoisXML API Email Verification API?

On our scheduled checks, WhoisXML API Email Verification API leads on measured uptime — Free Public APIs API at —% versus WhoisXML API Email Verification API 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 Free Public APIs API and WhoisXML API Email Verification API need an API key?

Free Public APIs API needs no key, while WhoisXML API Email Verification API requires a free API key. If you want to start calling without signup, reach for Free Public APIs API first.

Can I call Free Public APIs API and WhoisXML API Email Verification API from the browser?

Yes — both Free Public APIs API and WhoisXML API Email Verification API 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 Free Public APIs API and WhoisXML API Email Verification API free for commercial use?

Free Public APIs API has unclear commercial terms, and WhoisXML API Email Verification 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.