caldays vs The Muse

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

Uptime · 30d
Uptime · 90d—%—%
Uptime · 30d—%—%
P50 · ms
P95 · ms
Authnonenone
CORSyesno
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedUnverified
Free tierFree — limits not publishedFree tier — API key required
Rate limitUnpublishedUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

caldays vs The Muse: common questions

Which is more reliable, caldays or The Muse?

On our scheduled checks, The Muse leads on measured uptime — caldays at —% versus The Muse at —% over 90 days. These are our own probe results, not provider claims; the uptime bars above show the day-by-day record for both.

Do caldays and The Muse need an API key?

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

Can I call caldays and The Muse from the browser?

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

Are caldays and The Muse free for commercial use?

caldays has unclear commercial terms, and The Muse 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.