Calendar APIs

Calendar and scheduling services

13 APIs in this category · last checked 2 October 2026
13
APIs listed
9
need no API key (69%)
0
CORS enabled (0%)
12
HTTPS (92%)

This directory lists 13 calendar APIs. Use the filters below to narrow by authentication, HTTPS support and CORS. Every entry shows whether it needs authentication, serves over HTTPS and allows cross-origin requests, so you can pick one that fits your stack before you read a single doc page.

Showing 13 of 13 APIs

Church Calendar

Returns the Catholic liturgical calendar for any day, including season, liturgical color and celebrations, in Czech, Latin or English, free with no signup.

Auth: No HTTPS CORS: Unknown

Czech Namedays Calendar

Looks up the Czech name day for any given date and returns the corresponding name, a small free lookup service with no API key or signup required.

Auth: No HTTPS CORS: Unknown

Abstract Public Holidays

Returns national, regional and religious holidays for 200 plus countries and 3500 plus regions from year 1 to 2050, needs an API key, free tier allows 1000 calls a month.

Auth: apiKey HTTPS CORS: Unknown

Calendarific

Delivers holiday and observance data for 230 plus countries and 3300 plus regions in over 100 languages, needs an API key, free tier capped at 500 calls per month.

Auth: apiKey HTTPS CORS: Unknown

Holidays

Supplies holiday data for 250 plus countries and 3600 plus regions in 100 plus languages, needs an API key, free tier available with no credit card to sign up.

Auth: apiKey HTTPS CORS: Unknown

Nager.Date

Open source, community run service returning public holidays as JSON for dozens of countries, no API key needed and free to use without registration.

Auth: No HTTPS CORS: Unknown

Namedays Calendar

Returns name day dates for multiple countries and regions from a single free lookup service, no API key or registration required to query it.

Auth: No HTTPS CORS: Unknown

UK Bank Holidays

Official UK government feed of bank holidays for England and Wales, Scotland and Northern Ireland from 2019 through 2028, free JSON with no key needed.

Auth: No HTTPS CORS: Unknown

Hebrew Calendar

Converts between Gregorian and Hebrew dates and returns Shabbat times, holidays and zmanim, free with no signup, limited to 90 requests per 10 seconds.

Auth: No HTTPS CORS: Unknown

Non-Working Days (ICS)

GitHub hosted collection of auto generated ICS calendar files listing non working days for Belgium, France, Germany, Ireland, Switzerland, the UK and the US.

Auth: No HTTPS CORS: Unknown

LectServe

Publishes the ACNA Anglican daily and Sunday lectionary readings with links to the Bible passages, a small free site with no API key or signup needed.

Auth: No HTTPS CORS: Unknown

Google Calendar

Reads and writes Google Calendar events and calendars through a REST API, needs OAuth 2.0 authorization, free within Google Cloud's standard usage quota.

Auth: OAuth HTTPS CORS: Unknown

Non-Working Days API

Checks whether a date is a working, non working or short day in Russia, Kazakhstan, Belarus and Uzbekistan, free to query with no API key required.

Auth: No HTTPS CORS: Unknown

Best Calendar and Scheduling APIs for Developers

A calendar API allows developers to integrate scheduling, public holiday lookups, event management, and date utilities into their applications. These APIs eliminate the need to maintain your own holiday databases or build scheduling logic from scratch.

For public holidays without signup, start with Nager.Date, a free open source feed covering dozens of countries with no key needed. Abstract Public Holidays and Calendarific both need a key but their free tiers suit a side project, while the official UK Bank Holidays feed gives authoritative region by region data for free.

Religious calendars deserve their own pick: Hebcal is a mature source for Hebrew dates, Shabbat times and Jewish holidays, free but rate limited and licensed under attribution. The main pitfall here is freshness: holiday lists change yearly with substitute days and regional exceptions, so cache short and recheck before release. For scheduling rather than lookup, reach for the Google Calendar API instead.

What to check before you pick one

  • Country coverage: Holiday APIs should cover the regions your users are in, with accurate regional subdivision support.
  • iCal compatibility: APIs that return iCal format can be consumed by most calendar applications directly.
  • Timezone handling: Proper timezone support is essential for scheduling apps serving global users.

Frequently Asked Questions

What are calendar APIs?

Calendar APIs provide programmatic access to calendar data, public holiday schedules, scheduling services, event management, and date calculation utilities for integration into apps and workflows.

Is there a free API for public holidays?

Yes. APIs like Calendarific and Nager.Date provide free tiers for querying public holidays across dozens of countries, returning JSON data with holiday names and dates.

How do I integrate Google Calendar with my app?

The Google Calendar API uses OAuth 2.0. You register your app in Google Cloud Console, obtain credentials, and use the REST API or official SDKs to read and write calendar events on behalf of users.

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