IPMA vs wttr.in

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

Uptime · 30d
Uptime · 90d98.0%95.1%
Uptime · 30d96.7%98.3%
P50 · ms1024700
P95 · ms20344900
Authnonenone
CORSyesyes
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseIPMA open data (attribution 'Fonte: IPMA' expected)Unverified
Free tierFree, no keyFree — limits not published
Rate limitUnpublishedUnpublished (informal per-IP throttling)
In directory since2026-07-052026-07-05
operationalpartialdownno data

IPMA vs wttr.in: common questions

Which is more reliable, IPMA or wttr.in?

On our scheduled checks, IPMA leads on measured uptime — IPMA at 98.0% versus wttr.in at 95.1% 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, IPMA or wttr.in?

wttr.in has the lower median latency in our checks — IPMA responds in 1024 ms versus wttr.in at 700 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 IPMA and wttr.in need an API key?

Neither needs a paid key — IPMA is callable with no signup, and wttr.in is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call IPMA and wttr.in from the browser?

Yes — both IPMA and wttr.in 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 IPMA and wttr.in free for commercial use?

IPMA has unclear commercial terms, and wttr.in 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.