Calendarific provides a JSON API for all national holidays observed in all countries around the world.
Based on our record, Nextcloud Calendar should be more popular than Calendarific. It has been mentiond 4 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Https://date.nager.at/Api This is the only free one from what I can tell. There are a couple of paid ones https://www.abstractapi.com/holidays-api and https://calendarific.com/ with 1000/month free tiers so it'll depend on your use case. Source: about 2 years ago
Calendarific - Enterprise-grade Public holiday API service for over 200 countries. Free plan includes 1000 calls per month. - Source: dev.to / almost 3 years ago
Probably at nextcloud calendar app. Source: about 1 year ago
However, what you're describing seems like any simple Calendar will meet the needs (effectively, here's an event are you coming or not?). Might be overkill, but check out Nextcloud in that case (https://apps.nextcloud.com/apps/calendar). Source: about 1 year ago
I have moved from Google calendar to NextCloud calendar self-host and quite happy with it. I use it with Apple Calendar for creating events, etc. Though sometimes it doesn't sync properly, most of the time, it does the job. The only downside is, I would like to connect my domain/email to the calendar but it is not possible with NextCloud, so it is quite inconvenient if someone tries to invite me. Source: about 1 year ago
If you are a roll-your-own person, you could install and maintain a NextCloud server. See https://apps.nextcloud.com/apps/calendar and https://nextcloud.com/athome/ this is not for the faint of heart. Source: over 2 years ago
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