Convert dates accurately between the civil Gregorian calendar and the Jewish Hebrew calendar in either direction. Toggle sunset status, explore Hebrew month structures, and view corresponding days of the week, holidays, and weekly Torah readings.
How Bidirectional Conversion Works
Converting dates between civil and Hebrew calendars requires more than adding or subtracting a fixed number of years. The civil Gregorian calendar relies purely on the Earth’s orbit around the sun (365 or 366 days), while the Hebrew calendar is lunisolar, aligning months with lunar phases and years with solar seasons.
Our date converter handles bidirectional conversions with complete calendar accuracy:
- Gregorian to Hebrew Conversion: Evaluates the selected civil year, month, and day against lunar month calculations and applies your chosen sunset boundary (before or after sunset).
- Hebrew to Gregorian Conversion: Validates your selected Hebrew year, month, and day, ensuring that month length rules (such as 29 vs 30 days) and leap year structures are respected before returning the equivalent civil date.
- Contextual Metadata: Displays the day of the week, Hebrew year number (AM, Anno Mundi), related Jewish holidays, and the scheduled Shabbat Torah portion.
For full mathematical specifications of our conversion algorithms, consult our calculation methodology and open source data sources.
Important Considerations
When converting dates between calendar systems, several unique characteristics of the Hebrew calendar must be taken into account:
The Sunset Boundary
Because a Jewish day begins at sunset on the preceding civil evening, every civil calendar date overlaps with two distinct Hebrew dates. A civil date during morning and afternoon hours corresponds to one Hebrew date, but after sunset on that same civil day, the new Hebrew date begins. Selecting the correct sunset option ensures your conversion is precise.
Hebrew Leap Years (Adar I and Adar II)
The Hebrew calendar maintains alignment with solar seasons by inserting an extra 30-day month (Adar I) seven times every 19 years. During leap years, the standard month of Adar becomes Adar II. When converting from Hebrew to Gregorian during a leap year, ensure you select whether the date falls in Adar I or Adar II.
Variable Month Lengths
While civil months have 28 to 31 days, Hebrew months alternate between 29 days (deficient months) and 30 days (full months). Furthermore, the months of Cheshvan and Kislev vary in length depending on whether the Hebrew year is short (353-355 days) or full (383-385 days). Our converter validates month lengths automatically to prevent invalid date selections.
Frequently Asked Questions
Why does a civil date correspond to two different Hebrew dates?
A civil day runs from midnight to midnight, whereas a Hebrew day runs from sunset to sunset. Because sunset occurs in the late afternoon or evening, a single civil date includes the end of one Hebrew date (before sunset) and the beginning of the next Hebrew date (after sunset).
Why are there two Adar months in some Hebrew years?
To keep agricultural holidays aligned with their solar seasons (such as Passover in spring), the Hebrew calendar uses a 19-year cycle that adds a 13th month seven times every 19 years. During these leap years, Adar I is added before the standard Adar month, which is designated as Adar II.
How do I know if my birth or event occurred before or after sunset?
If the event took place during daylight hours (morning or afternoon), select before sunset. If it occurred in the evening after the sun dropped below the horizon, select after sunset. If the exact time is unknown, converting both possibilities will reveal the two candidate Hebrew dates.
What does the Hebrew year number (such as 5787) mean?
Hebrew years are counted according to the traditional Jewish era, Anno Mundi (AM), which counts years from the traditional Rabbinic calculation of creation. For example, the civil year 2026 coincides with parts of the Hebrew years 5786 and 5787.
Can I convert historical or far future dates?
Yes. Our converter supports dates spanning past, present, and future years, allowing you to convert historical family records or calculate upcoming milestone anniversaries decades in advance.
For detailed explanations of lunisolar calendar mechanics, read our complete Jewish calendar guide.
Access Specialized Calculators
Our converter serves as a central junction for specialized Hebrew calendar tools:
- Compute personal birth anniversaries with our Jewish birthday calculator.
- Plan milestone celebrations using our Bar & Bat Mitzvah calculator.
- Determine annual remembrance dates with our Yahrzeit calculator.
- View upcoming festival dates on our Jewish holidays calendar.
Use the converter above to easily translate any date between Gregorian and Hebrew calendars today.