User Agent Lookup API vs VATlayer
Same instrument, two spec sheets — measured, not claimed.
User Agent Lookup API vs VATlayer: common questions
Which is more reliable, User Agent Lookup API or VATlayer?
Both are neck-and-neck — User Agent Lookup API and VATlayer 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, User Agent Lookup API or VATlayer?
User Agent Lookup API has the lower median latency in our checks — User Agent Lookup API responds in 426 ms versus VATlayer at 473 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 User Agent Lookup API and VATlayer need an API key?
User Agent Lookup API needs no key, while VATlayer requires a free API key. If you want to start calling without signup, reach for User Agent Lookup API first.
Can I call User Agent Lookup API and VATlayer from the browser?
Neither sends browser-friendly CORS headers reliably, so call User Agent Lookup API and VATlayer from a server or proxy rather than client-side. The CORS and HTTPS rows above show exactly what we detected for each.
Are User Agent Lookup API and VATlayer free for commercial use?
User Agent Lookup API has unclear commercial terms, and VATlayer 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.