Aleph & Apricot
Israeli Culture

Hebrew Calendar Explained for Everyday Use

Aleph & Apricot · Updated 2026-07-19 · 4 min read
Hebrew Calendar Explained for Everyday Use
AbstractThe Hebrew calendar is lunisolar: its months follow lunar cycles, while leap years add a month to keep festivals aligned with their seasons. Ordinary years have 12 months and leap years have 13. Hebrew dates begin in the evening, so a holiday's practical start is often the prior Gregorian evening. Because conversions shift from year to year, use a current calendar rather than reusing last year's dates.
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The Hebrew calendar follows moon and sun

The Hebrew calendar is lunisolar: months follow lunar cycles, while leap years keep the festivals aligned with their seasons. An ordinary year has 12 months; a leap year adds a thirteenth. Because it does not match the Gregorian calendar day for day, Jewish holidays appear on different Gregorian dates each year.

The Jewish Virtual Library's calendar overview describes the calendar as primarily lunar and explains that an extra Adar is inserted within a fixed 19-year cycle to keep the months aligned with the solar seasons. Use a current converter for an actual date rather than calculating the cycle from this summary.

The calendar is used for Jewish holidays, religious life, memorial dates, birthdays, and public scheduling in Israel alongside the Gregorian calendar.

Learn the month sequence

The civil year commonly begins with Tishrei, followed by Cheshvan, Kislev, Tevet, Shevat, Adar, Nisan, Iyar, Sivan, Tammuz, Av, and Elul. In a leap year, an additional month called Adar I is inserted before the existing Adar, which is then called Adar II.

Religious texts can count months from Nisan while numbering years from Tishrei. That sounds like two calendars arguing over the first chair, but it is one calendar with more than one starting convention.

Month lengths can vary within the calendar's rules, so do not calculate a distant date by repeatedly adding a fixed number of days. Use a reliable converter or published calendar.

A date begins in the evening

Jewish calendar dates begin at evening, not midnight. A holiday listed as the 15th of a Hebrew month therefore starts the previous Gregorian evening. Exact religious times depend on local sunset and observance.

This matters for invitations, closures, travel, and greetings. If your itinerary says a festival is “on Tuesday,” the practical change may begin Monday evening. The Shabbat guide applies the same evening-to-evening logic each week.

Read Hebrew dates and numbers

Hebrew dates may be written with ordinary digits or Hebrew letters used numerically. Month names can appear in Hebrew, transliteration, or English. For travel planning, write both calendars on one line and include the evening start:

Gregorian date | Hebrew date | begins previous evening | local opening notes

Do not assume two English spellings indicate different months. Cheshvan/Heshvan and Tevet/Teveth are transliteration variants, not secret bonus seasons.

Why leap years matter

Twelve lunar months are shorter than a solar year. The added month keeps Passover in spring and the wider festival cycle aligned with its seasonal framework. The Hebrew calendar follows a fixed leap-year cycle; use a reliable current calendar or converter rather than calculating a date from memory.

You do not need to memorize the cycle to plan a dinner. You do need a current calendar when converting dates. In a leap year, which Adar carries a birthday, yahrzeit, or other personal observance can depend on community practice, so confirm it with the family or community concerned.

Use the calendar in context

Our overview of Jewish holidays in Israel shows how dates affect meals, services, and public life. The holiday travel planner turns calendar knowledge into practical checks for transport, attractions, and accommodation.

Different Jewish communities may observe some dates, customs, or additional festival days differently, especially inside and outside Israel. Civil commemorations and other religious calendars also shape life in the country. Treat the Hebrew calendar as an essential layer, not the only calendar anyone uses.

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FAQ

Why do Jewish holidays change dates each year?

Their Hebrew dates remain fixed, but the Hebrew lunisolar calendar does not align day for day with the Gregorian solar calendar. When converted, the Gregorian date therefore shifts. A leap month periodically keeps the festivals in their seasonal framework. Always check the year and remember that observance begins the prior evening.

How many months are in the Hebrew calendar?

An ordinary Hebrew year has 12 months. A leap year has 13, adding Adar I before Adar II. The calendar uses seven leap years within a repeating 19-year cycle. Month lengths can also vary within established rules, so accurate conversion is best done with a current published calendar or calculator.

When does a Hebrew calendar day begin?

A Hebrew date begins in the evening. That means a holiday identified with a particular daytime date starts the previous Gregorian evening. Exact religious start times are linked to local sunset and community practice. For invitations and travel, record both the listed date and the preceding evening to avoid a one-day planning error.