Free Calendar APIs with no API key

15 Calendar APIs that need no API key, account or credit card. 7 of them also allow CORS, so you can call them straight from browser JavaScript. Listed by uptime and ease of use.

1. 1

   caldays API

   Online · 867 ms

   Public holidays for 195+ countries.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
2. 2

   CountdownsHQ API

   Online · 623 ms

   Dates and timezone-correct countdowns for 150+ holidays and observances in 18 countries.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
3. 3

   The Calendar API

   Online · 643 ms

   Public holidays for US states and 30 countries plus sports and finance calendars as static JSON.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
4. 4

   UK Bank Holidays API

   Online · 62 ms

   Bank holidays in England and Wales, Scotland and Northern Ireland.

   • No API key needed
   • Fast: 62 ms response
   • Returns JSON at its URL
   • HTTPS

   No authHTTPSCORS ?
5. 5

   India Public Holidays API

   Online · 459 ms

   Official Indian public holidays for the Central government and 36 states/UTs.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
6. 6

   Intellibook API

   Online · 1280 ms

   Appointment booking and availability API for salons and clinics.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
7. 7N

   Namedays Calendar API

   Online · 616 ms

   Provides namedays for multiple countries.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
8. 8

   Non-Working Days API

   Online · 2770 ms

   Simple REST API for checking working, non-working or short days for Russia, CIS, USA and other.

   • No API key needed
   • Callable from the browser (CORS)
   • HTTPS

   No authHTTPSCORS
9. 9

   Non-Working Days API

   Online · 565 ms

   Database of ICS files for non working days.

   • No API key needed
   • HTTPS

   No authHTTPSCORS ?
10. 10

    Nager.Date API

    Online · 1111 ms

    Public holidays for more than 90 countries.

    • No API key needed
    • HTTPS

    No authHTTPSNo CORS
11. 11

    Russian Calendar API

    Online · 661 ms

    Check if a date is a Russian holiday or not.

    • No API key needed
    • HTTPS

    No authHTTPSNo CORS
12. 12

    Hebrew Calendar API

    Online · 819 ms

    Convert between Gregorian and Hebrew, fetch Shabbat and Holiday times, etc.

    • No API key needed

    No authNo HTTPSCORS ?
13. 13C

    Church Calendar API

    Online · 405 ms

    Catholic liturgical calendar. A free calendar API by calapi.inadiutorium.cz.

    • No API key needed

    No authNo HTTPSCORS ?
14. 14C

    Czech Namedays Calendar API

    Last check failed

    Lookup for a name and returns nameday date.

    • No API key needed

    No authNo HTTPSCORS ?
15. 15

    LectServe API

    Last check failed

    Protestant liturgical calendar. A free calendar API by lectserve.com.

    • No API key needed

    No authNo HTTPSCORS ?

Keyless Calendar APIs compared

Calendar APIs with no API key

API	API key	HTTPS	CORS	Uptime	Response	Rating
caldays	No	Yes	Yes	Up	867 ms	Not rated
CountdownsHQ	No	Yes	Yes	Up	623 ms	Not rated
The Calendar	No	Yes	Yes	Up	643 ms	Not rated
UK Bank Holidays	No	Yes	Unknown	Up	62 ms	Not rated
India Public Holidays	No	Yes	Yes	Up	459 ms	Not rated
Intellibook	No	Yes	Yes	Up	1280 ms	Not rated
NNamedays Calendar	No	Yes	Yes	Up	616 ms	Not rated
Non-Working Days	No	Yes	Yes	Up	2770 ms	Not rated
Non-Working Days	No	Yes	Unknown	Up	565 ms	Not rated
Nager.Date	No	Yes	No	Up	1111 ms	Not rated
Russian Calendar	No	Yes	No	Up	661 ms	Not rated
Hebrew Calendar	No	No	Unknown	Up	819 ms	Not rated
CChurch Calendar	No	No	Unknown	Up	405 ms	Not rated
CCzech Namedays Calendar	No	No	Unknown	Down	–	Not rated
LectServe	No	No	Unknown	Down	–	Not rated

See also: best Calendar APIs · all 22 Calendar APIs · every API with no key