EmailRep vs National Vulnerability Database

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

Uptime · 30d
Uptime · 90d100%91.6%
Uptime · 30d100%93.1%
P50 · ms132263
P95 · ms7514448
Authnonenone
CORSnoyes
HTTPSyesyes
Card requirednono
Commercial useunclearyes
Data licenseUnverifiedPublic domain (U.S. Government work)
Free tierFree — limits not publishedFree — no key required (free key raises limits)
Rate limitUnpublished5 requests per rolling 30 seconds without an API key (50 with a free key)
In directory since2026-07-052026-07-05
operationalpartialdownno data

EmailRep vs National Vulnerability Database: common questions

Which is more reliable, EmailRep or National Vulnerability Database?

On our scheduled checks, EmailRep leads on measured uptime — EmailRep at 100% versus National Vulnerability Database at 91.6% 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, EmailRep or National Vulnerability Database?

EmailRep has the lower median latency in our checks — EmailRep responds in 132 ms versus National Vulnerability Database at 263 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 EmailRep and National Vulnerability Database need an API key?

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

Can I call EmailRep and National Vulnerability Database from the browser?

Only National Vulnerability Database is browser-friendly — it returns CORS headers over HTTPS. EmailRep needs a server-side call or proxy, so factor that into which one fits a front-end project.

Are EmailRep and National Vulnerability Database free for commercial use?

EmailRep has unclear commercial terms, and National Vulnerability Database 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.