Namedays Calendar vs OpenHolidays API
Same instrument, two spec sheets — measured, not claimed.
Namedays Calendar vs OpenHolidays API: common questions
Which is more reliable, Namedays Calendar or OpenHolidays API?
On our scheduled checks, OpenHolidays API leads on measured uptime — Namedays Calendar at 91.2% versus OpenHolidays API 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, Namedays Calendar or OpenHolidays API?
Namedays Calendar has the lower median latency in our checks — Namedays Calendar responds in 480 ms versus OpenHolidays API at 533 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 Namedays Calendar and OpenHolidays API need an API key?
Neither needs a paid key — Namedays Calendar is callable with no signup, and OpenHolidays API is callable with no signup. Both are quick to prototype with; rate limits still apply.
Can I call Namedays Calendar and OpenHolidays API from the browser?
Only OpenHolidays API is browser-friendly — it returns CORS headers over HTTPS. Namedays Calendar needs a server-side call or proxy, so factor that into which one fits a front-end project.
Are Namedays Calendar and OpenHolidays API free for commercial use?
Namedays Calendar has unclear commercial terms, and OpenHolidays 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.