
source code credit
Hi,
I am building a Garmin hebrew calendar implementation. I will include the below credits for some of the code that helped me. Would you also want me to put the Monkey C code into your repository, or is the credit enough? I have no probelm sharing, but functionality is limited by watch capabilities right now.
This implementation is using code based on the HebCal (https://www.hebcal.com) APIs.
While I do not call their API directly, I have used their source code (https://hebcal.github.io/api/hdate/modules.html) to help build some of my functionality.
The use of such code is based on CC BY 4.0 International License, and does not imply endorsement from HebCal.

Hi, thanks for contacting Hebcal.
The @hebcal/hdate JavaScript source code that you are referencing is licensed under the GPL-2.0 license
https://github.com/hebcal/hdate-js?tab=GPL-2.0-1-ov-file#readme
If you are reusing source code to build your functionality, please be sure to note the The GNU General Public License 2.0 requirements.
The CC BY 4.0 license applies to content generated by web APIs, but not for source code reuse.

Adjustments before Hillel II, and before 7-900?
This is awesome! However, I was wondering: Does this calculator make adjustments for years before Hillel II when the calendar was different, and/or before the change in the years which used to track time since the Exodus rather than from Creation?

Thanks for using Hebcal. In short, no, you should not look to Hebcal to give precise calculations for dates before 1752 CE. Hebcal uses the proleptic Gregorian calendar and does not attempt to compensate for dates that differ prior to the Gregorian reformation.

CORS error on accessing www.hebcal.com/yahrzeit
I am trying to implement the returnd of info using Yahrzeti + Anniversary REST API. I am coding in Javascript in an HTML page so I have modified the code to use a FETCH in an aynchronous funciion with POST and other typical parameters. Howver I encounter an CORS error for cross platform issues. THe web page is embedded into a page available for inserted web pages on an application site so I have no control of the site or parts of the page outside the section I am adding. The chorme defugger lists the following when it tries to do the fetch .
A cross-origin resource sharing (CORS) request was blocked because of invalid or missing response headers of the request or the associated preflight request. To fix this issue, ensure the response to the CORS request and/or the associated preflight request are not missing headers and use valid header values. Note that if an opaque response is sufficient, the request's mode can be set to no-cors to fetch the resource with CORS disabled; that way CORS headers are not required but the response content is inaccessible (opaque).
1 request
Request Status Preflight Request (if problematic) Header Problem Invalid Value (if available)
yahrzeit blocked Access-Control-Allow-Origin Missing Header clude'
I am somewhat out of my league on this one. I have successfully loaded the HebCal Yz form that returns an observatin date from values entered on the form. Just dumped the code into a section of my blank HTML code section with the Hebcal HTML and it worked. But inserting equivalent JS to the CURL calls does not. Anyone who has implemented this type of API cal for JavaScxript on a web page please respond.

Thank you for using the Hebcal developer APIs. We apologize for the missing CORS header on our Yahrzeit + Anniversary web API. This was indeed a misconfiguration on our end.
This error is now fixed on our end. You should be able to access this API and your browser will receive the correct
Access-Control-Allow-Origin header.

Building a calendar for approx 30 individuals
We have a community minyan and want to build a database as described in the Header.
So I don't have to reinvent the wheel perhaps the methodology is available.
I want some sort of login protection and the capability for individuals to add and edit their dagtes

Hi, thanks for using Hebcal.
You are welcome to use the free Yahrzeit + Anniversary calendar located at https://www.hebcal.com/yahrzeit
This webiste was designed for individuals, not minyanim, so it's quite limited in its features and offers only a few options for customization. We definitely don't have all of the the features you described. For example, there is no login protection - only an "unlisted link" mechanism that permits anyone who has the link to edit the page. At this time, we don't have plans to add additional features like logins, nor do we have any capability to offer any further customization of the current product.
Feel free to use our existing tool as it is, or consider a commercial solution like ShulCloud for your minyan.
Shana Tova and G'mar Chatima Tova!

fasting days are not included in the calendar
added the calendar to my outlook but the fasting days are not included

Urgent suggestion
I wanted to share the Oct 2024 calendar with my boss to show the Yom Tov dates. If you click on sukkot it says Yom Tov is like the sabbath and “work” is not permitted. Please include that statement for when you click on EACH one of the Yom tovim.

is 5785 a leap year? Vayakhel-Pekudei is both separate weeks and a double in the selections on the Torah tab
I wanted to know if 5785 is a leap year.
I tried checking the first double portion to see if it was doubled. It was on March 22. But, then if I select Vayakhel as in a leap year, it comes up on the 22 of March, and Pekudei comes up on the 29th. I can't figure out which is correct.

Thanks for the feedback. We see how this was confusing.
The page was giving the date and linking to the Vayakhel (single parsha) for 2025. We have corrected it so it now more clearly displays the following:
Parashat Vayakhel-Pekudei is the 22nd and 23rd weekly Torah portion in the annual Jewish cycle of Torah reading. Next read on14 Mar 2026 / 25 Adar 5786.

Weekday diaspora 5785 spreadsheet inaccuracy
The weekday diaspora 5785 spreadsheet inaccurately shows Breishit as the weekday reading for the week between Rosh Hashanah and Yom Kippur, when it should be Vezot Habracha. It is also unclear as a result of this what the Monday reading before Sukkot should be. Please fix this, our daily minyan depends on this amazing tool!

Thank you for using Hebcal and thanks for contacting us about this error in the weekday leyning spreadsheets.
Another user reported this error and we fixed the spreadsheets on Friday right before Shabbat. If you check again, you will see the following corrected readings, which concur with the conservative Luach Hashana 5785 published by Rabbi Miles Cohen
Date | Parashah | Weekday Aliyah | Reading |
7-Oct-24 | Vezot Haberakhah | 1 | Deuteronomy 33:1-33:7 |
7-Oct-24 | Vezot Haberakhah | 2 | Deuteronomy 33:8-33:12 |
7-Oct-24 | Vezot Haberakhah | 3 | Deuteronomy 33:13-33:17 |
10-Oct-24 | Vezot Haberakhah | 1 | Deuteronomy 33:1-33:7 |
10-Oct-24 | Vezot Haberakhah | 2 | Deuteronomy 33:8-33:12 |
10-Oct-24 | Vezot Haberakhah | 3 | Deuteronomy 33:13-33:17 |
14-Oct-24 | Vezot Haberakhah | 1 | Deuteronomy 33:1-33:7 |
14-Oct-24 | Vezot Haberakhah | 2 | Deuteronomy 33:8-33:12 |
14-Oct-24 | Vezot Haberakhah | 3 | Deuteronomy 33:13-33:17 |
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