caldays vs Lobsters

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

Uptime · 30d
Uptime · 90d100%100%
Uptime · 30d100%100%
P50 · ms149245
P95 · ms6751175
Authnonenone
CORSyesno
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedUnverified
Free tierFree — limits not publishedFree — limits not published
Rate limitUnpublishedUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

caldays vs Lobsters: common questions

Which is more reliable, caldays or Lobsters?

Both are neck-and-neck — caldays and Lobsters 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, caldays or Lobsters?

caldays has the lower median latency in our checks — caldays responds in 149 ms versus Lobsters at 245 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 caldays and Lobsters need an API key?

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

Can I call caldays and Lobsters from the browser?

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

Are caldays and Lobsters free for commercial use?

caldays has unclear commercial terms, and Lobsters 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.