AQICN vs US Weather
Same instrument, two spec sheets — measured, not claimed.
AQICN vs US Weather: common questions
Which is more reliable, AQICN or US Weather?
Both are neck-and-neck — AQICN and US Weather 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, AQICN or US Weather?
US Weather has the lower median latency in our checks — AQICN responds in 224 ms versus US Weather at 223 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 AQICN and US Weather need an API key?
US Weather needs no key, while AQICN requires a free API key. If you want to start calling without signup, reach for US Weather first.
Can I call AQICN and US Weather from the browser?
Only US Weather is browser-friendly — it returns CORS headers over HTTPS. AQICN needs a server-side call or proxy, so factor that into which one fits a front-end project.
Are AQICN and US Weather free for commercial use?
AQICN has unclear commercial terms, and US Weather 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.