Open-Meteo vs Website Carbon

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

Uptime · 30d
Uptime · 90d94.1%100%
Uptime · 30d91.7%100%
P50 · ms67437
P95 · ms1193166
Authnonenone
CORSyesno
HTTPSyesyes
Card requirednono
Commercial usenounclear
Data licenseCC-BY 4.0Unverified
Free tier<10,000 calls/day, no signupFree keyless byte-based /data endpoint
Rate limit600/min · 5,000/hourUnpublished
In directory since2026-05-022026-07-05
operationalpartialdownno data

Open-Meteo vs Website Carbon: common questions

Which is more reliable, Open-Meteo or Website Carbon?

On our scheduled checks, Website Carbon leads on measured uptime — Open-Meteo at 94.1% versus Website Carbon at 100% 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, Open-Meteo or Website Carbon?

Website Carbon has the lower median latency in our checks — Open-Meteo responds in 674 ms versus Website Carbon at 37 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 Open-Meteo and Website Carbon need an API key?

Neither needs a paid key — Open-Meteo is callable with no signup, and Website Carbon is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call Open-Meteo and Website Carbon from the browser?

Only Open-Meteo is browser-friendly — it returns CORS headers over HTTPS. Website Carbon needs a server-side call or proxy, so factor that into which one fits a front-end project.

Are Open-Meteo and Website Carbon free for commercial use?

Open-Meteo is personal/non-commercial only, and Website Carbon 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.