Category Archives: Yahrzeits and Anniversaries

We are pleased to offer support for REST API for personal Yahrzeits, Hebrew Birthdays and Hebrew Anniversaries.

Note that this is a web API with the same functionality as the getYahrzeit and getBirthdayOrAnniversary APIs provided by the JavaScript @hebcal/core package. If you’re building a JavaScript application, consider using the native JS library instead of web APIs for a faster user experience.

Clients should POST x-www-form-urlencoded data to https://www.hebcal.com/yahrzeit

Regarding application/x-www-form-urlencoded: the keys and values are encoded in key-value tuples separated by '&', with a '=' between the key and the value. Non-alphanumeric characters in both keys and values are percent encoded.

The following parameters must be specified

• cfg=json
• v=yahrzeit

The following parameters may be specified once

• years=3 – default 20. Use years=1 for only a single Hebrew year
• hebdate=on – append Hebrew date to the event titles (default off)
• yizkor=on – Include Yizkor dates (default off)
  • i=off – Diaspora Yizkor schedule (Pesach 8th day, Shavuot 2nd day, Yom Kippur and Shmini Atzeret)
  • i=on – Israel Yizkor schedule (Pesach 7th day, Shavuot, Yom Kippur and Shmini Atzeret)
• start=5749 – beginning Hebrew year to calculate anniversary dates (defaults the current Hebrew year)
• end=5761 – ending Hebrew year (inclusive) to calculate anniversary dates (defaults to start year + years years)
• hdp=1 – include heDateParts field on untimed (all-day) items in the response

Then, specify at least one input date based on the Gregorian date of death (or birth). The following parameters are required, substituting the X with increasing integers beginning with 1.

• yX=1983 – Gregorian year, 4-digit date
• mX=4 – Gregorian month (1=January, 12=December; leading zeros optional)
• dX=15 – Gregorian day of month (1-31; leading zeros optional)
• sX=on – Event occurred on Gregorian date after sunset (default off implies that event occurred before sunset)
• tX=Yahrzeit – type (either Yahrzeit, Birthday or Anniversary – case-sensitive)
• nX=Plonit+ben+Ploni – name (optional)

Please take care to specify the correct tX type parameter (either Yahrzeit, Birthday or Anniversary). The algorithm (according to Ashkenazic practice) differs between these options, especially in the months of Adar, Cheshvan, or Kislev. For more information, see “How does Hebcal determine anniversaries (birthdays, yahrzeits)?“

Unlike other Hebcal.com REST APIs, this API requires HTTPS (either HTTP/1.1 or HTTP/2) due to the personal/sensitive nature of the information being passed across the Internet.

• We support both gzip and br (brotli) compression; set the appropriate Accept-Encoding header in your request to enable
• We support HTTP Keep-Alive for multiple requests

Example

Here is an example of two events, a Hebrew Birthday for Person1 and a Yahrzeit for Person2:

curl \
  -X POST \
  -H 'Content-Type: application/x-www-form-urlencoded' \
  --compressed \
  --data-raw 'cfg=json&v=yahrzeit&n1=Person1&t1=Birthday&d1=15&m1=4&y1=1983&s1=on&n2=Person2&t2=Yahrzeit&d2=13&m2=11&y2=2008&s2=off&hebdate=on&years=3' \
  https://www.hebcal.com/yahrzeit

The response will be application/json that looks like this:

{
  "title": "Hebrew Anniversaries: Person1, Person2",
  "date": "2022-05-30T19:04:58.561Z",
  "range": {
    "start": "2021-10-21",
    "end": "2024-05-11"
  },
  "items": [
    {
      "title": "Person2's 13th Yahrzeit (15th of Cheshvan)",
      "date": "2021-10-21",
      "hdate": "15 Cheshvan 5782",
      "memo": "Hebcal joins you in remembering Person2, whose 13th Yahrzeit occurs on Thursday, October 21, corresponding to the 15th of Cheshvan, 5782.\n\nPerson2's Yahrzeit begins at sundown on Wednesday, October 20 and continues until sundown on the day of observance. It is customary to light a memorial candle at sundown as the Yahrzeit begins.\n\nMay your loved one's soul be bound up in the bond of eternal life and may their memory serve as a continued source of inspiration and comfort to you.",
      "name": "Person2",
      "category": "yahrzeit",
      "anniversary": 13
    },
    {
      "title": "Person1's 39th Hebrew Birthday (3rd of Iyyar)",
      "date": "2022-05-04",
      "hdate": "3 Iyyar 5782",
      "memo": "Hebcal joins you in honoring Person1, whose 39th Hebrew Birthday occurs on Wednesday, May 4, corresponding to the 3rd of Iyyar, 5782.\n\nPerson1's Hebrew Birthday begins at sundown on Tuesday, May 3 and continues until sundown on the day of observance.",
      "name": "Person1",
      "category": "birthday",
      "anniversary": 39
    },
    {
      "title": "Person2's 14th Yahrzeit (15th of Cheshvan)",
      "date": "2022-11-09",
      "hdate": "15 Cheshvan 5783",
      "memo": "Hebcal joins you in remembering Person2, whose 14th Yahrzeit occurs on Wednesday, November 9, corresponding to the 15th of Cheshvan, 5783.\n\nPerson2's Yahrzeit begins at sundown on Tuesday, November 8 and continues until sundown on the day of observance. It is customary to light a memorial candle at sundown as the Yahrzeit begins.\n\nMay your loved one's soul be bound up in the bond of eternal life and may their memory serve as a continued source of inspiration and comfort to you.",
      "name": "Person2",
      "category": "yahrzeit",
      "anniversary": 14
    },
    {
      "title": "Person1's 40th Hebrew Birthday (3rd of Iyyar)",
      "date": "2023-04-24",
      "hdate": "3 Iyyar 5783",
      "memo": "Hebcal joins you in honoring Person1, whose 40th Hebrew Birthday occurs on Monday, April 24, corresponding to the 3rd of Iyyar, 5783.\n\nPerson1's Hebrew Birthday begins at sundown on Sunday, April 23 and continues until sundown on the day of observance.",
      "name": "Person1",
      "category": "birthday",
      "anniversary": 40
    },
    {
      "title": "Person2's 15th Yahrzeit (15th of Cheshvan)",
      "date": "2023-10-30",
      "hdate": "15 Cheshvan 5784",
      "memo": "Hebcal joins you in remembering Person2, whose 15th Yahrzeit occurs on Monday, October 30, corresponding to the 15th of Cheshvan, 5784.\n\nPerson2's Yahrzeit begins at sundown on Sunday, October 29 and continues until sundown on the day of observance. It is customary to light a memorial candle at sundown as the Yahrzeit begins.\n\nMay your loved one's soul be bound up in the bond of eternal life and may their memory serve as a continued source of inspiration and comfort to you.",
      "name": "Person2",
      "category": "yahrzeit",
      "anniversary": 15
    },
    {
      "title": "Person1's 41st Hebrew Birthday (3rd of Iyyar)",
      "date": "2024-05-11",
      "hdate": "3 Iyyar 5784",
      "memo": "Hebcal joins you in honoring Person1, whose 41st Hebrew Birthday occurs on Saturday, May 11, corresponding to the 3rd of Iyyar, 5784.\n\nPerson1's Hebrew Birthday begins at sundown on Friday, May 10 and continues until sundown on the day of observance.",
      "name": "Person1",
      "category": "birthday",
      "anniversary": 41
    }
  ]
}

You may use these HTML tags to insert a small form directly on your web page, with a reverse link back to your site:

Make sure you replace both the ref_url and ref_text value fields with with your own synagogue’s.