Hi all, we made a small change to our server configuration to permit API requests like this work without requiring HTTPS.

This should fix older versions of the widget.

Happy Chanukah!

We accept some advertisements through Google AdSense. We have configured Google AdSense to block certain categories of advertisements that we feel do not belong on Hebcal.com (“Video Games”, “Alcohol”, “Gambling & Betting”,“Dating”, “Cosmetic Procedures & Body Modification”, among others). We also block advertisements from Christian and Messianic Judaism organizations.

To show your ads specifically on Hebcal.com, you should use a feature in Google Ads called Placement Targeting. Since Hebcal participates in AdSense, it is part of the Google Display Network (GDN), meaning you can "hand-pick" it as a destination for your ads.

Here is the step-by-step process to set this up:

1. Create a Display Campaign

Placement targeting is primarily available for Display Network campaigns.

• Log in to your Google Ads account.
• Click the + button and select New Campaign.
• Choose a goal (like "Website traffic" or "Brand awareness") or select "Create a campaign without a goal's guidance."
• Select Display as your campaign type.

2. Navigate to Content Targeting

Once you are setting up your Ad Group (or editing an existing one):

• Scroll down to the Content section.
• Look for the dropdown or menu labeled Placements.
• Click Add placements.

3. Target hebcal.com

• Select the Enter tab (rather than "Search").
• Type or paste hebcal.com into the box.
• Click Add 1 placement.
• Note: You can also target specific sub-pages if you only want your ads to appear on the "Shabbat Times" or "Yahrzeit" pages by entering the specific URL (e.g., hebcal.com/shabbat).

4. Adjust Targeting Settings ("Targeting" vs. "Observation")

This is a critical step to ensure your ads only show on Hebcal:

• Ensure your setting is set to Targeting.
• If you select "Observation," Google will show ads on Hebcal but also to your specified audience across the entire web. By selecting Targeting, you are restricting the campaign so it only serves ads when a user is on the specific sites you listed.

Important Considerations

• Inventory Competition: Even if you target a site, your ad isn't guaranteed to show every time. You are still competing in an auction against other advertisers. If Hebcal is popular, you may need to increase your CPM (Cost Per Mille) or CPC (Cost Per Click) bid to win the slot.
• Ad Sizes: Hebcal typically uses standard banner sizes. To maximize your chances of appearing, upload your creative in multiple formats, such as:
  • Medium Rectangle: 300 x 250
  • Leaderboard: 728 x 90
  • Wide Skyscraper: 160 x 600
• Traffic Volume: If the specific page you target has low traffic, your ads may not serve many impressions. It is often helpful to target the entire domain (hebcal.com) rather than just one specific URL.

Thanks for using Hebcal! To download holidays and candle-lighting times, navigate to https://www.hebcal.com/hebcal and fill out the form with your preferences (including specifying your location in the Candle-lighting & Fast times section of the form).

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.

Converting between Hebrew and Gregorian dates for very early years is mathematically possible (and is supported by our Hebrew Date Converter), but the results should be treated as approximations rather than historically precise dates.

The Hebrew calendar evolved into a fixed, calculation-based system beginning in the 4th century CE, traditionally associated with reforms attributed to Hillel II (a fifth generation amora). This shift replaced earlier dependence on eyewitness moon sightings and centralized rulings on leap years with a predictable mathematical framework. The detailed rules were recorded in writing over the following centuries and were later systematized by Maimonides in the 12th century, by which point the calendar had become uniform across Jewish communities by the medieval era.^[1]

Before the calendar rules were fully standardized in the early medieval period, both the Hebrew and civil calendars were influenced by local practice, observational methods, and later retroactive calculations. As a result, modern algorithms can project dates backward consistently, but they may not reflect how dates were actually observed or recorded at the time.

Any results for year 1752 CE and earlier published on Hebcal.com will be inaccurate. Hebcal does not take into account a correction of ten days that was introduced by Pope Gregory XIII known as the Gregorian Reformation.

yes! Please use our  Yahrzeits, Birthday, and Anniversary calendar. 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 »

Your DNS server is caching IP addresses much longer than it should. We changed our IP address more than 24 hours ago, and for some reason your Internet Service Provider is not respecting standard DNS Time-To-Live.

$ host www.hebcal.com
www.hebcal.com is an alias for www-vip.hebcal.com.
www-vip.hebcal.com has address 129.212.148.210

If you're running your own DNS and caching beyond standard TTLs, flush your cache. Otherwise, ask your ISP to follow Internet standards.

We are not blocking your IP address.

Your DNS server is caching IP addresses much longer than it should. We changed our IP address more than 24 hours ago, and for some reason your Internet Service Provider is not respecting standard DNS Time-To-Live.

$ host www.hebcal.com
www.hebcal.com is an alias for www-vip.hebcal.com.
www-vip.hebcal.com has address 129.212.148.210

If you're running your own DNS and caching beyond standard TTLs, flush your cache. Otherwise, ask your ISP to follow Internet standards.