Overview
Pass an integer month to fetch Catholic celebrations for the current year. Each response includes the event rank, liturgical season, vestment color, and whether the date is a holy day of obligation. Paid plans can specify custom years and receive additional lectionary cycles, psalter weeks, and season boundary dates.
Endpoint
One host, one path per API. The block below shows this call in four languages; every one of them is the same HTTP request. Making requests covers the timeouts, retries and parameter rules that apply to all of them. The SDKs wrap the same call in a typed client.
curl "https://api.apiverve.com/v1/liturgicalcalendar?month=2&year=2025" \
-H "x-api-key: your_api_key_here"const res = await fetch('https://api.apiverve.com/v1/liturgicalcalendar?month=2&year=2025', {
headers: { 'x-api-key': 'your_api_key_here' },
});
if (!res.ok) throw new Error(`${res.status} ${await res.text()}`);
const { data } = await res.json();
console.log(data);import requests
res = requests.get(
"https://api.apiverve.com/v1/liturgicalcalendar?month=2&year=2025",
headers={"x-api-key": "your_api_key_here"},
timeout=15,
)
res.raise_for_status()
print(res.json()["data"])package main
import (
"fmt"
"io"
"net/http"
)
func main() {
req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/liturgicalcalendar?month=2&year=2025", nil)
req.Header.Set("x-api-key", "your_api_key_here")
res, err := http.DefaultClient.Do(req)
if err != nil {
panic(err)
}
defer res.Body.Close()
out, _ := io.ReadAll(res.Body)
fmt.Println(string(out))
}Replace your_api_key_here with the key from your dashboard. When the inputs arrive as a list rather than one at a time, batch requests run up to 200 of them through this same API in a single call.
Authentication
Send your key in the x-api-key header. That is the only auth step — there is no token exchange and no per-endpoint scope to configure. Authentication covers creating, rotating and revoking keys.
401 is the only auth verdict
A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.
Parameters
Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them.
| Parameter | Type | Description |
|---|---|---|
monthOptional | integer | The month to get Liturgical Calendar data for (default: current month) range 1–12 |
yearOptionalPremium | integer | The year to get Liturgical Calendar data for (default: current year) range 1900–2100 |
Response
Every API returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape. Response format covers the envelope, the other output formats and how premium fields are withheld.
{
"status": "ok",
"error": null,
"data": {
"2026-01-01": [
{
"id": "mary_mother_of_god",
"precedence": "GENERAL_SOLEMNITY_3",
"rank": "SOLEMNITY",
"isHolyDayOfObligation": true,
"isOptional": false,
"colors": [
"WHITE"
]
}
],
"2026-01-02": [
{
"id": "basil_the_great_and_gregory_nazianzen_bishops",
"precedence": "GENERAL_MEMORIAL_10",
"rank": "MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
],
"weekday": {
"id": "christmas_time_january_2",
"date": "2026-01-02",
"dateDef": {
"dateFn": "weekdayBeforeEpiphany",
"dateArgs": [
2
],
"yearOffset": 0
},
"dateExceptions": [],
"alternativeTransferDateDefs": [],
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"allowSimilarRankItems": false,
"isHolyDayOfObligation": false,
"isOptional": false,
"i18nDef": [
"seasons:christmas_time.before_epiphany",
{
"day": 2
}
],
"seasons": [
"CHRISTMAS_TIME"
],
"periods": [
"DAYS_BEFORE_EPIPHANY",
"CHRISTMAS_TO_PRESENTATION_OF_THE_LORD"
],
"colors": [
"WHITE"
],
"commonsDef": [],
"martyrology": [],
"titles": [],
"calendar": {
"weekOfSeason": 2,
"dayOfSeason": 9,
"dayOfWeek": 5,
"nthDayOfWeekInMonth": 1,
"startOfSeason": "2025-12-25",
"endOfSeason": "2026-01-11",
"startOfLiturgicalYear": "2025-11-30",
"endOfLiturgicalYear": "2026-11-28",
"seasons": [
"CHRISTMAS_TIME"
]
},
"cycles": {
"properCycle": "PROPER_OF_TIME",
"sundayCycle": "YEAR_A",
"weekdayCycle": "YEAR_2",
"psalterWeek": "WEEK_1"
},
"fromCalendarId": "ProperOfTime",
"fromExtendedCalendars": []
}
}
],
"2026-01-03": [
{
"id": "christmas_time_january_3",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
]
},
{
"id": "most_holy_name_of_jesus",
"precedence": "OPTIONAL_MEMORIAL_12",
"rank": "OPTIONAL_MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": true,
"colors": [
"WHITE"
],
"weekday": {
"id": "christmas_time_january_3",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
]
}
}
],
"2026-01-04": [
{
"id": "second_sunday_after_christmas",
"precedence": "UNPRIVILEGED_SUNDAY_6",
"rank": "SUNDAY",
"isHolyDayOfObligation": true,
"isOptional": false,
"colors": [
"WHITE"
]
}
],
"2026-01-05": [
{
"id": "christmas_time_january_5",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
]
}
],
"2026-01-06": [
{
"id": "epiphany_of_the_lord",
"precedence": "PROPER_OF_TIME_SOLEMNITY_2",
"rank": "SOLEMNITY",
"isHolyDayOfObligation": true,
"isOptional": false,
"colors": [
"WHITE"
]
}
],
"2026-01-07": [
{
"id": "wednesday_after_epiphany",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
]
},
{
"id": "raymond_of_penyafort_priest",
"precedence": "OPTIONAL_MEMORIAL_12",
"rank": "OPTIONAL_MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": true,
"colors": [
"WHITE"
],
"weekday": {
"id": "wednesday_after_epiphany",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
]
}
}
],
"2026-01-08": [
{
"id": "thursday_after_epiphany",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
]
}
],
"2026-01-09": [
{
"id": "friday_after_epiphany",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
]
}
],
"2026-01-10": [
{
"id": "saturday_after_epiphany",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
]
}
],
"2026-01-11": [
{
"id": "baptism_of_the_lord",
"precedence": "PROPER_OF_TIME_SOLEMNITY_2",
"rank": "SOLEMNITY",
"isHolyDayOfObligation": true,
"isOptional": false,
"colors": [
"WHITE"
]
}
],
"2026-01-12": [
{
"id": "ordinary_time_1_monday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
],
"2026-01-13": [
{
"id": "ordinary_time_1_tuesday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
},
{
"id": "hilary_of_poitiers_bishop",
"precedence": "OPTIONAL_MEMORIAL_12",
"rank": "OPTIONAL_MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": true,
"colors": [
"WHITE"
],
"weekday": {
"id": "ordinary_time_1_tuesday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
}
],
"2026-01-14": [
{
"id": "ordinary_time_1_wednesday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
],
"2026-01-15": [
{
"id": "ordinary_time_1_thursday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
],
"2026-01-16": [
{
"id": "ordinary_time_1_friday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
],
"2026-01-17": [
{
"id": "anthony_of_egypt_abbot",
"precedence": "GENERAL_MEMORIAL_10",
"rank": "MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
],
"weekday": {
"id": "ordinary_time_1_saturday",
"date": "2026-01-17",
"dateDef": {
"dateFn": "dateOfOrdinaryTime",
"dateArgs": [
6,
1
],
"yearOffset": 0
},
"dateExceptions": [],
"alternativeTransferDateDefs": [],
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"allowSimilarRankItems": false,
"isHolyDayOfObligation": false,
"isOptional": false,
"i18nDef": [
"seasons:ordinary_time.weekday",
{
"week": 1,
"dow": 6
}
],
"seasons": [
"ORDINARY_TIME"
],
"periods": [
"EARLY_ORDINARY_TIME"
],
"colors": [
"GREEN"
],
"commonsDef": [],
"martyrology": [],
"titles": [],
"calendar": {
"weekOfSeason": 1,
"dayOfSeason": 6,
"dayOfWeek": 6,
"nthDayOfWeekInMonth": 3,
"startOfSeason": "2026-01-12",
"endOfSeason": "2026-11-28",
"startOfLiturgicalYear": "2025-11-30",
"endOfLiturgicalYear": "2026-11-28",
"seasons": [
"ORDINARY_TIME"
]
},
"cycles": {
"properCycle": "PROPER_OF_TIME",
"sundayCycle": "YEAR_A",
"weekdayCycle": "YEAR_2",
"psalterWeek": "WEEK_1"
},
"fromCalendarId": "ProperOfTime",
"fromExtendedCalendars": []
}
}
],
"2026-01-18": [
{
"id": "ordinary_time_2_sunday",
"precedence": "UNPRIVILEGED_SUNDAY_6",
"rank": "SUNDAY",
"isHolyDayOfObligation": true,
"isOptional": false,
"colors": [
"GREEN"
]
}
],
"2026-01-19": [
{
"id": "ordinary_time_2_monday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
],
"2026-01-20": [
{
"id": "ordinary_time_2_tuesday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
},
{
"id": "fabian_i_pope",
"precedence": "OPTIONAL_MEMORIAL_12",
"rank": "OPTIONAL_MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": true,
"colors": [
"RED"
],
"weekday": {
"id": "ordinary_time_2_tuesday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
},
{
"id": "sebastian_of_milan_martyr",
"precedence": "OPTIONAL_MEMORIAL_12",
"rank": "OPTIONAL_MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": true,
"colors": [
"RED"
],
"weekday": {
"id": "ordinary_time_2_tuesday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
}
],
"2026-01-21": [
{
"id": "agnes_of_rome_virgin",
"precedence": "GENERAL_MEMORIAL_10",
"rank": "MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"RED"
],
"weekday": {
"id": "ordinary_time_2_wednesday",
"date": "2026-01-21",
"dateDef": {
"dateFn": "dateOfOrdinaryTime",
"dateArgs": [
3,
2
],
"yearOffset": 0
},
"dateExceptions": [],
"alternativeTransferDateDefs": [],
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"allowSimilarRankItems": false,
"isHolyDayOfObligation": false,
"isOptional": false,
"i18nDef": [
"seasons:ordinary_time.weekday",
{
"week": 2,
"dow": 3
}
],
"seasons": [
"ORDINARY_TIME"
],
"periods": [
"EARLY_ORDINARY_TIME"
],
"colors": [
"GREEN"
],
"commonsDef": [],
"martyrology": [],
"titles": [],
"calendar": {
"weekOfSeason": 2,
"dayOfSeason": 10,
"dayOfWeek": 3,
"nthDayOfWeekInMonth": 3,
"startOfSeason": "2026-01-12",
"endOfSeason": "2026-11-28",
"startOfLiturgicalYear": "2025-11-30",
"endOfLiturgicalYear": "2026-11-28",
"seasons": [
"ORDINARY_TIME"
]
},
"cycles": {
"properCycle": "PROPER_OF_TIME",
"sundayCycle": "YEAR_A",
"weekdayCycle": "YEAR_2",
"psalterWeek": "WEEK_2"
},
"fromCalendarId": "ProperOfTime",
"fromExtendedCalendars": []
}
}
],
"2026-01-22": [
{
"id": "ordinary_time_2_thursday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
},
{
"id": "vincent_of_saragossa_deacon",
"precedence": "OPTIONAL_MEMORIAL_12",
"rank": "OPTIONAL_MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": true,
"colors": [
"RED"
],
"weekday": {
"id": "ordinary_time_2_thursday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
}
],
"2026-01-23": [
{
"id": "ordinary_time_2_friday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
],
"2026-01-24": [
{
"id": "francis_de_sales_bishop",
"precedence": "GENERAL_MEMORIAL_10",
"rank": "MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
],
"weekday": {
"id": "ordinary_time_2_saturday",
"date": "2026-01-24",
"dateDef": {
"dateFn": "dateOfOrdinaryTime",
"dateArgs": [
6,
2
],
"yearOffset": 0
},
"dateExceptions": [],
"alternativeTransferDateDefs": [],
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"allowSimilarRankItems": false,
"isHolyDayOfObligation": false,
"isOptional": false,
"i18nDef": [
"seasons:ordinary_time.weekday",
{
"week": 2,
"dow": 6
}
],
"seasons": [
"ORDINARY_TIME"
],
"periods": [
"EARLY_ORDINARY_TIME"
],
"colors": [
"GREEN"
],
"commonsDef": [],
"martyrology": [],
"titles": [],
"calendar": {
"weekOfSeason": 2,
"dayOfSeason": 13,
"dayOfWeek": 6,
"nthDayOfWeekInMonth": 4,
"startOfSeason": "2026-01-12",
"endOfSeason": "2026-11-28",
"startOfLiturgicalYear": "2025-11-30",
"endOfLiturgicalYear": "2026-11-28",
"seasons": [
"ORDINARY_TIME"
]
},
"cycles": {
"properCycle": "PROPER_OF_TIME",
"sundayCycle": "YEAR_A",
"weekdayCycle": "YEAR_2",
"psalterWeek": "WEEK_2"
},
"fromCalendarId": "ProperOfTime",
"fromExtendedCalendars": []
}
}
],
"2026-01-25": [
{
"id": "sunday_of_the_word_of_god",
"precedence": "UNPRIVILEGED_SUNDAY_6",
"rank": "SUNDAY",
"isHolyDayOfObligation": true,
"isOptional": false,
"colors": [
"GREEN"
]
}
],
"2026-01-26": [
{
"id": "timothy_of_ephesus_and_titus_of_crete_bishops",
"precedence": "GENERAL_MEMORIAL_10",
"rank": "MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
],
"weekday": {
"id": "ordinary_time_3_monday",
"date": "2026-01-26",
"dateDef": {
"dateFn": "dateOfOrdinaryTime",
"dateArgs": [
1,
3
],
"yearOffset": 0
},
"dateExceptions": [],
"alternativeTransferDateDefs": [],
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"allowSimilarRankItems": false,
"isHolyDayOfObligation": false,
"isOptional": false,
"i18nDef": [
"seasons:ordinary_time.weekday",
{
"week": 3,
"dow": 1
}
],
"seasons": [
"ORDINARY_TIME"
],
"periods": [
"EARLY_ORDINARY_TIME"
],
"colors": [
"GREEN"
],
"commonsDef": [],
"martyrology": [],
"titles": [],
"calendar": {
"weekOfSeason": 3,
"dayOfSeason": 15,
"dayOfWeek": 1,
"nthDayOfWeekInMonth": 4,
"startOfSeason": "2026-01-12",
"endOfSeason": "2026-11-28",
"startOfLiturgicalYear": "2025-11-30",
"endOfLiturgicalYear": "2026-11-28",
"seasons": [
"ORDINARY_TIME"
]
},
"cycles": {
"properCycle": "PROPER_OF_TIME",
"sundayCycle": "YEAR_A",
"weekdayCycle": "YEAR_2",
"psalterWeek": "WEEK_3"
},
"fromCalendarId": "ProperOfTime",
"fromExtendedCalendars": []
}
}
],
"2026-01-27": [
{
"id": "ordinary_time_3_tuesday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
},
{
"id": "angela_merici_virgin",
"precedence": "OPTIONAL_MEMORIAL_12",
"rank": "OPTIONAL_MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": true,
"colors": [
"WHITE"
],
"weekday": {
"id": "ordinary_time_3_tuesday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
}
],
"2026-01-28": [
{
"id": "thomas_aquinas_priest",
"precedence": "GENERAL_MEMORIAL_10",
"rank": "MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
],
"weekday": {
"id": "ordinary_time_3_wednesday",
"date": "2026-01-28",
"dateDef": {
"dateFn": "dateOfOrdinaryTime",
"dateArgs": [
3,
3
],
"yearOffset": 0
},
"dateExceptions": [],
"alternativeTransferDateDefs": [],
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"allowSimilarRankItems": false,
"isHolyDayOfObligation": false,
"isOptional": false,
"i18nDef": [
"seasons:ordinary_time.weekday",
{
"week": 3,
"dow": 3
}
],
"seasons": [
"ORDINARY_TIME"
],
"periods": [
"EARLY_ORDINARY_TIME"
],
"colors": [
"GREEN"
],
"commonsDef": [],
"martyrology": [],
"titles": [],
"calendar": {
"weekOfSeason": 3,
"dayOfSeason": 17,
"dayOfWeek": 3,
"nthDayOfWeekInMonth": 4,
"startOfSeason": "2026-01-12",
"endOfSeason": "2026-11-28",
"startOfLiturgicalYear": "2025-11-30",
"endOfLiturgicalYear": "2026-11-28",
"seasons": [
"ORDINARY_TIME"
]
},
"cycles": {
"properCycle": "PROPER_OF_TIME",
"sundayCycle": "YEAR_A",
"weekdayCycle": "YEAR_2",
"psalterWeek": "WEEK_3"
},
"fromCalendarId": "ProperOfTime",
"fromExtendedCalendars": []
}
}
],
"2026-01-29": [
{
"id": "ordinary_time_3_thursday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
],
"2026-01-30": [
{
"id": "ordinary_time_3_friday",
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"GREEN"
]
}
],
"2026-01-31": [
{
"id": "john_bosco_priest",
"precedence": "GENERAL_MEMORIAL_10",
"rank": "MEMORIAL",
"isHolyDayOfObligation": false,
"isOptional": false,
"colors": [
"WHITE"
],
"weekday": {
"id": "ordinary_time_3_saturday",
"date": "2026-01-31",
"dateDef": {
"dateFn": "dateOfOrdinaryTime",
"dateArgs": [
6,
3
],
"yearOffset": 0
},
"dateExceptions": [],
"alternativeTransferDateDefs": [],
"precedence": "WEEKDAY_13",
"rank": "WEEKDAY",
"allowSimilarRankItems": false,
"isHolyDayOfObligation": false,
"isOptional": false,
"i18nDef": [
"seasons:ordinary_time.weekday",
{
"week": 3,
"dow": 6
}
],
"seasons": [
"ORDINARY_TIME"
],
"periods": [
"EARLY_ORDINARY_TIME"
],
"colors": [
"GREEN"
],
"commonsDef": [],
"martyrology": [],
"titles": [],
"calendar": {
"weekOfSeason": 3,
"dayOfSeason": 20,
"dayOfWeek": 6,
"nthDayOfWeekInMonth": 5,
"startOfSeason": "2026-01-12",
"endOfSeason": "2026-11-28",
"startOfLiturgicalYear": "2025-11-30",
"endOfLiturgicalYear": "2026-11-28",
"seasons": [
"ORDINARY_TIME"
]
},
"cycles": {
"properCycle": "PROPER_OF_TIME",
"sundayCycle": "YEAR_A",
"weekdayCycle": "YEAR_2",
"psalterWeek": "WEEK_3"
},
"fromCalendarId": "ProperOfTime",
"fromExtendedCalendars": []
}
}
]
}
}
Response fields
Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.
| Field | Type | Example | Description |
|---|---|---|---|
2026-01-01 | array[1] | ||
id | string | "mary_mother_of_god" | Unique identifier naming the liturgical event; also labels the nested weekday object when one is present |
precedencePremium | string | "GENERAL_SOLEMNITY_3" | Liturgical rank precedence level that determines which of several events on the same date is actually observed |
rank | string | "SOLEMNITY" | Liturgical rank classification of the event (e.g., WEEKDAY, MEMORIAL, FEAST, SOLEMNITY, SUNDAY) |
isHolyDayOfObligation | boolean | true | Whether Catholics are obligated to attend Mass for this event |
isOptional | boolean | false | Whether observing this event is left to choice rather than required, as with an optional memorial |
colors | array | [WHITE] | Liturgical vestment colors worn for the event (e.g., PURPLE, WHITE, RED, GREEN) |
2026-01-02 | array[1] | ||
id | string | "basil_the_great_and_gregory_nazianzen_bishops" | Unique identifier naming the liturgical event; also labels the nested weekday object when one is present |
precedencePremium | string | "GENERAL_MEMORIAL_10" | Liturgical rank precedence level that determines which of several events on the same date is actually observed |
rank | string | "MEMORIAL" | Liturgical rank classification of the event (e.g., WEEKDAY, MEMORIAL, FEAST, SOLEMNITY, SUNDAY) |
isHolyDayOfObligation | boolean | false | Whether Catholics are obligated to attend Mass for this event |
isOptional | boolean | false | Whether observing this event is left to choice rather than required, as with an optional memorial |
colors | array | [WHITE] | Liturgical vestment colors worn for the event (e.g., PURPLE, WHITE, RED, GREEN) |
weekday | object | {...} | The plain weekday this date would otherwise observe; present when the listed event is a memorial or optional memorial that takes precedence over, or is offered as an alternative to, the ordinary weekday |
id | string | "christmas_time_january_2" | Unique identifier naming the liturgical event; also labels the nested weekday object when one is present |
date | string | "2026-01-02" | |
dateDef | object | {...} | |
dateFn | string | "weekdayBeforeEpiphany" | |
dateArgs | array | [2] | |
yearOffset | number | 0 | |
dateExceptions | array | [] | |
alternativeTransferDateDefs | array | [] | |
precedencePremium | string | "WEEKDAY_13" | Liturgical rank precedence level that determines which of several events on the same date is actually observed |
rank | string | "WEEKDAY" | Liturgical rank classification of the event (e.g., WEEKDAY, MEMORIAL, FEAST, SOLEMNITY, SUNDAY) |
allowSimilarRankItems | boolean | false | |
isHolyDayOfObligation | boolean | false | Whether Catholics are obligated to attend Mass for this event |
isOptional | boolean | false | Whether observing this event is left to choice rather than required, as with an optional memorial |
i18nDef | array | [seasons:christmas_time.before_epiphany, ...] | |
seasons | array | [CHRISTMAS_TIME] | |
periods | array | [DAYS_BEFORE_EPIPHANY, ...] | |
colors | array | [WHITE] | Liturgical vestment colors worn for the event (e.g., PURPLE, WHITE, RED, GREEN) |
commonsDef | array | [] | |
martyrology | array | [] | |
titles | array | [] | |
calendar | object | {...} | |
weekOfSeason | number | 2 | |
dayOfSeason | number | 9 | |
dayOfWeek | number | 5 | |
nthDayOfWeekInMonth | number | 1 | |
startOfSeason | string | "2025-12-25" | |
endOfSeason | string | "2026-01-11" | |
startOfLiturgicalYear | string | "2025-11-30" | |
endOfLiturgicalYear | string | "2026-11-28" | |
seasons | array | [CHRISTMAS_TIME] | |
cycles | object | {...} | |
properCycle | string | "PROPER_OF_TIME" | |
sundayCycle | string | "YEAR_A" | |
weekdayCycle | string | "YEAR_2" | |
psalterWeek | string | "WEEK_1" | |
fromCalendarId | string | "ProperOfTime" | |
fromExtendedCalendars | array | [] | |
2026-01-03 | array[2] | ||
id | string | "christmas_time_january_3" | Unique identifier naming the liturgical event; also labels the nested weekday object when one is present |
precedencePremium | string | "WEEKDAY_13" | Liturgical rank precedence level that determines which of several events on the same date is actually observed |
rank | string | "WEEKDAY" | Liturgical rank classification of the event (e.g., WEEKDAY, MEMORIAL, FEAST, SOLEMNITY, SUNDAY) |
isHolyDayOfObligation | boolean | false | Whether Catholics are obligated to attend Mass for this event |
isOptional | boolean | false | Whether observing this event is left to choice rather than required, as with an optional memorial |
colors | array | [WHITE] | Liturgical vestment colors worn for the event (e.g., PURPLE, WHITE, RED, GREEN) |
2026-01-04 | array[1] | ||
id | string | "second_sunday_after_christmas" | Unique identifier naming the liturgical event; also labels the nested weekday object when one is present |
precedencePremium | string | "UNPRIVILEGED_SUNDAY_6" | Liturgical rank precedence level that determines which of several events on the same date is actually observed |
rank | string | "SUNDAY" | Liturgical rank classification of the event (e.g., WEEKDAY, MEMORIAL, FEAST, SOLEMNITY, SUNDAY) |
isHolyDayOfObligation | boolean | true | Whether Catholics are obligated to attend Mass for this event |
isOptional | boolean | false | Whether observing this event is left to choice rather than required, as with an optional memorial |
colors | array | [WHITE] | Liturgical vestment colors worn for the event (e.g., PURPLE, WHITE, RED, GREEN) |
2026-01-05 | array[1] | ||
id | string | "christmas_time_january_5" | Unique identifier naming the liturgical event; also labels the nested weekday object when one is present |
precedencePremium | string | "WEEKDAY_13" | Liturgical rank precedence level that determines which of several events on the same date is actually observed |
rank | string | "WEEKDAY" | Liturgical rank classification of the event (e.g., WEEKDAY, MEMORIAL, FEAST, SOLEMNITY, SUNDAY) |
isHolyDayOfObligation | boolean | false | Whether Catholics are obligated to attend Mass for this event |
isOptional | boolean | false | Whether observing this event is left to choice rather than required, as with an optional memorial |
colors | array | [WHITE] | Liturgical vestment colors worn for the event (e.g., PURPLE, WHITE, RED, GREEN) |
2026-01-06 | array[1] | ||
id | string | "epiphany_of_the_lord" | Unique identifier naming the liturgical event; also labels the nested weekday object when one is present |
precedencePremium | string | "PROPER_OF_TIME_SOLEMNITY_2" | Liturgical rank precedence level that determines which of several events on the same date is actually observed |
rank | string | "SOLEMNITY" | Liturgical rank classification of the event (e.g., WEEKDAY, MEMORIAL, FEAST, SOLEMNITY, SUNDAY) |
isHolyDayOfObligation | boolean | true | Whether Catholics are obligated to attend Mass for this event |
isOptional | boolean | false | Whether observing this event is left to choice rather than required, as with an optional memorial |
colors | array | [WHITE] | Liturgical vestment colors worn for the event (e.g., PURPLE, WHITE, RED, GREEN) |
Errors
Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change. Error handling covers the full status list and which of them are worth retrying.
| Status | Meaning | What to do |
|---|---|---|
400 | Input was rejected | Read error; it names the parameter. |
401 | Key missing or invalid | Check the header name and the key value. |
403 | Key valid, but not permitted | A key restriction or IP allow-list; see key scoping. |
429 | Rate limited, or out of credits | Read error to tell them apart; see rate limits. |
Use cases
- Church Bulletin Publishing
- When preparing weekly parish bulletins, church administrators pull upcoming feast ranks and vestment colors to format worship aids accurately.
- Daily Missal Apps
- Mobile prayer apps display daily commemorations and required vestment colors to orient users within the current Catholic season.
- Sacristy Vestment Planning
- To prepare altar paraments and priest vestments ahead of time, sacristans check the required liturgical color for upcoming celebrations.
- Catholic School Scheduling
- School administrators schedule all-school masses by checking which upcoming dates qualify as holy days of obligation.
Other ways to use Liturgical Calendar
Set up Liturgical Calendar on APIVerve, or reach the same source a different way. Your APIVerve account and credits work on all of them — one key, one balance.
Give it to an AI agentConnect over MCP and your agent calls it as a native tool — Claude, Cursor, ChatGPT.VerveKit →Reference →
Google Sheets or ExcelA =VERVE() formula fills a column — no script, no export, recalculates in place.VerveSheets →Reference →
Ground an agent on itA cited, machine-checkable fact your model can't produce on its own.VerveContext →Reference →
Related
More in Calendar: