Aare.guru API vs Hong Kong Observatory

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

Uptime · 30d
Uptime · 90d100%98.9%
Uptime · 30d100%96.6%
P50 · ms2331678
P95 · ms29934276
Authnonenone
CORSyesyes
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedHKO open data (see terms of use)
Free tierFree — limits not publishedFree, no key
Rate limitUnpublishedUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

Aare.guru API vs Hong Kong Observatory: common questions

Which is more reliable, Aare.guru API or Hong Kong Observatory?

On our scheduled checks, Aare.guru API leads on measured uptime — Aare.guru API at 100% versus Hong Kong Observatory at 98.9% 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, Aare.guru API or Hong Kong Observatory?

Aare.guru API has the lower median latency in our checks — Aare.guru API responds in 233 ms versus Hong Kong Observatory at 1678 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 Aare.guru API and Hong Kong Observatory need an API key?

Neither needs a paid key — Aare.guru API is callable with no signup, and Hong Kong Observatory is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call Aare.guru API and Hong Kong Observatory from the browser?

Yes — both Aare.guru API and Hong Kong Observatory 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 Aare.guru API and Hong Kong Observatory free for commercial use?

Aare.guru API has unclear commercial terms, and Hong Kong Observatory 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.