Thanks for getting back to me. We need to first do the lower-level Zmanim integration. We have to do a small amount of porting from KosherZmanim/KosherJava because that 4-year-old package depends on the bloated Luxon library; our fork uses the new JS Temporal. 

Once that's done, it should be more straightforward to add a "Chabad" checkbox to the Hebcal Custom Calendar creator, and a Chabad option for the iCalendar feed for Zmanim.

Again, no promises on when - this is probably a day or two of work. We'll keep this ticket open and update as we make progress and have something for you to test.

Thanks for this suggestion. We will endeavor to add these to the Hebcal TypeScript libraries. We can't promise a date by when we will complete these - Hebcal is a volunteer gig, not our day job.

Would you expect to use these as a software developer via web APIs like our Zmanim (halachic times) API, or as an end user with some sort of web pages and calendar feeds? 

Note that we don't currently have any Zmanim web pages on hebcal.com, and our iCalendar feed for Zmanim is considered experimental and doesn't really have a proper web UI. The hebcal.com website is currently more focused on holidays, date conversion, Yahrzeits, and Torah readings. It only exposes a very limited subset of zmanim (candle-lighting, havdalah, and fast start/end times) to end users via the custom calendar creator feature.

We have added this feed to to https://www.hebcal.com/ical/ 

Thank you for this reference 

Encyclopædia Britannica has an excellent introduction to the Jewish calendar. Another well written treatment of the Jewish calendar can be found in Understanding the Jewish Calendar by Rabbi Nathan Bushwick.

Calendars created by Hebcal are easily downloaded and imported into various calendar apps, including iPhone, Google Calendar, Outlook PC, Outlook Web, macOS Calendar, and any app that supports iCalendar (.ics) feeds or subscriptions.

The calendar apps from big companies (Google, Apple, Microsoft) all support the ability to view multiple calendar feeds together in a single view.

Because you probably already use one of these calendar apps, the easiest way for you to merge multiple Yahrzeit calendars together is to leave them as separate calendars on the Hebcal side and then visualize them as merged calendars in your destination calendar app.

We don’t have any plans to add a merge feature to the Hebcal Yahrzeit + Anniversary Calendar.

Hi, if you want just candle lighting, havdalah, and fast start/end times, you can use our iPhone instructions here

https://www.hebcal.com/home/77/iphone-ipad-jewish-holidays

If you are looking for other halachic times. we have an experimental zmanim calendar feed with some instructions here

https://www.hebcal.com/home/4522/zmanim-icalendar-feed

Configuration is quite a bit more tricky as this is not really a fully finished feature. you need to be comfortable editing URLs and will need to either use your ZIP code if you live in the USA or find your geoname id on the Hebcal website

Yahrzeits and Birthdays

Create a personal list of Yahrzeit (memorial) and Yizkor dates, Hebrew Birthdays and Anniversaries for 20+ years. Free annual email reminders & calendar downloads.

Get started »

thanks for using Hebcal!

Pages generated by the Interactive Jewish Calendarcan be printed very easily on standard 8.5×11″ paper. Just try “Print Preview” and you’ll see what it looks like. You can print out an entire year at a time and each month will end up on a separate sheet.

We also offer a simple Print PDF feature that creates PDF files in landscape layout, one page per month.

To print other sizes or to customize, we recommend downloading/exporting from hebcal.com and importing into a more full-featured desktop or web calendar program, such as one of the following:

• Outlook CSV – Outlook has extremely powerful print features (Daily, Weekly, Monthly, Tri-fold, Calendar Details, Day-Timer, Day Runner, Franklin Day Planner, etc.)
• Google Calendar – offers Day, Week, Month, or Agenda views with customizable date range, font size, page orientation, and color setting (see also “Print your calendar” from Google support)
• Apple macOS Calendar – offers Day, Week, Month, List, Selected Events in US Letter and other standard paper formats. Options include All-day events, Timed events, Color/Black and white, and text size controls.

OK, the initial version is online. Take a look and tell us if it looks good to you!

https://www.hebcal.com/hebcal?v=1&dpy=on&start=2025-02-01&end=2025-12-31&set=off