caldays vs OpenHolidays API
Same instrument, two spec sheets — measured, not claimed.
caldays vs OpenHolidays API: common questions
Which is more reliable, caldays or OpenHolidays API?
On our scheduled checks, OpenHolidays API leads on measured uptime — caldays at —% versus OpenHolidays 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 caldays and OpenHolidays API need an API key?
Neither needs a paid key — caldays 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 caldays and OpenHolidays API from the browser?
Yes — both caldays and OpenHolidays 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 caldays and OpenHolidays API free for commercial use?
caldays 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.