ReqRes vs User Agent Lookup API

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

Uptime · 30d
Uptime · 90d—%—%
Uptime · 30d—%—%
P50 · ms
P95 · ms
Authnonenone
CORSnono
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

ReqRes vs User Agent Lookup API: common questions

Which is more reliable, ReqRes or User Agent Lookup API?

On our scheduled checks, User Agent Lookup API leads on measured uptime — ReqRes at —% versus User Agent Lookup 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 ReqRes and User Agent Lookup API need an API key?

Neither needs a paid key — ReqRes is callable with no signup, and User Agent Lookup API is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call ReqRes and User Agent Lookup API from the browser?

Neither sends browser-friendly CORS headers reliably, so call ReqRes and User Agent Lookup API from a server or proxy rather than client-side. The CORS and HTTPS rows above show exactly what we detected for each.

Are ReqRes and User Agent Lookup API free for commercial use?

ReqRes has unclear commercial terms, and User Agent Lookup 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.