Catholic Liturgical Calendar

API /calendar endpoint

Collection of Liturgical events for any given year between 1970 and 9999. The base /calendar path returns liturgical events for the General Roman Calendar. National and Diocesan calendars can be requested on the /calendar/nation/{NATION} and /calendar/diocese/{DIOCESE} paths respectively. Each of these paths can optionally be further specified with a /{YEAR} path parameter. When not specified, the API will default to the current year.

Path builder
Request parameters available on the base /calendar path
These parameters are useful for tweaking the calendar results, when no National or Diocesan calendar is requested. Since National and Diocesan calendars have these parameters built in, the parameters are not available on the /calendar/nation/{NATION} and /calendar/diocese/{DIOCESE} routes.
N.B. When none of these parameters are set, the API will use the defaults as in use in the Vatican.
Request parameters available on all /calendar/* paths
These request parameters can always be set, whether we are requesting the base /calendar resource or any resource below the /calendar path. National and Diocesan calendars do not have these parameters built-in.
https://litcal.johnromanodorazio.com/api/dev/calendar
URL of the API request based on selected options. The button is set to the same URL, click on it to see results.
Liturgical Calendar Validator
In order to verify that the liturgical data produced by the API is correct, there is a Unit Test interface that can run predefined tests against the JSON responses produced by the API starting from the year 1970 and going up to 25 years from the current year.
The unit tests are defined in the LiturgicalCalendarAPI/tree/development/tests folder in the Liturgical Calendar API repository. The unit test interface is curated in a repository of its own: Liturgical-Calendar/UnitTestInterface.
Translation Tool
Translations status

Translations status

Open API Schema

All of the available API routes with their supported methods, parameters, content types and responses are described here.

Calculation of the Date of Easter: API

A simple API endpoint that returns data about the Date of Easter, both Gregorian and Julian, from 1583 (year of the adoption of the Gregorian Calendar) to 9999 (maximum possible date calculation in 64bit PHP), using a PHP adaptation of the Meeus/Jones/Butcher algorithm for Gregorian easter (observed by the Roman Catholic church) and of the Meeus algorithm for Julian easter (observed by orthodox churches).

Currently the data can be requested with almost any localization. In any case, since the API returns a UNIX timestamp for each date of Easter, localizations can be done in a client application just as well.