Namedays Calendar vs The SMS Works API

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

Uptime · 30d
Uptime · 90d—%—%
Uptime · 30d—%—%
P50 · ms
P95 · ms
AuthnoneapiKey
CORSyesyes
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

Namedays Calendar vs The SMS Works API: common questions

Which is more reliable, Namedays Calendar or The SMS Works API?

On our scheduled checks, The SMS Works API leads on measured uptime — Namedays Calendar at —% versus The SMS Works API 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 Namedays Calendar and The SMS Works API need an API key?

Namedays Calendar needs no key, while The SMS Works API requires a free API key. If you want to start calling without signup, reach for Namedays Calendar first.

Can I call Namedays Calendar and The SMS Works API from the browser?

Yes — both Namedays Calendar and The SMS Works API 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 Namedays Calendar and The SMS Works API free for commercial use?

Namedays Calendar has unclear commercial terms, and The SMS Works API 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.