The Biblical Calendar
Twelve months, each with its own name, meaning, and appointed days. Explore the whole biblical year — or find the Hebrew month you were born in.
The Hebrew calendar has twelve months in an ordinary year and thirteen in a leap year. Each one begins at the new moon — the Hebrew word for month, chodesh (חֹדֶשׁ), comes fromchadash, "new." The biblical year opens with Nisan in the spring, the month God set apart when He told Moses, "This month shall be the beginning of months" (Exodus 12:2). The Jewish civil year opens six months later with Tishrei, at Rosh Hashanah. Both counts are ancient, and both are used to this day — which is why the same month can be called the seventh or the first depending on which year you are counting.
Listed below in the biblical order, beginning with Nisan. The Gregorian column is approximate by design: the Hebrew calendar follows the moon, so each month drifts a few weeks against the Western calendar from year to year while staying anchored to its season.
| # | Month | Hebrew | Meaning | Falls in | Days | Tribe |
|---|---|---|---|---|---|---|
| 1 | Nisan | נִיסָן | Month of Miracles | March–April | 30 | Judah |
| 2 | Iyar | אִיָּר | Month of Healing | April–May | 29 | Issachar |
| 3 | Sivan | סִיוָן | Month of Revelation | May–June | 30 | Zebulun |
| 4 | Tammuz | תַּמּוּז | Month of Vision | June–July | 29 | Reuben |
| 5 | Av | אָב | Month of the Father | July–August | 30 | Simeon |
| 6 | Elul | אֱלוּל | Month of Repentance | August–September | 29 | Gad |
| 7 | Tishrei | תִּשְׁרֵי | Month of New Beginnings | September–October | 30 | Ephraim |
| 8 | Cheshvan | חֶשְׁוָן | Month of the Flood | October–November | 29 or 30 | Manasseh |
| 9 | Kislev | כִּסְלֵו | Month of Dreams | November–December | 30 or 29 | Benjamin |
| 10 | Tevet | טֵבֵת | Month of Immersion | December–January | 29 | Dan |
| 11 | Shevat | שְׁבָט | Month of the Trees | January–February | 30 | Asher |
| 12 | Adar | אֲדָר | Month of Joy | February–March | 29 | Naphtali |
Cheshvan and Kislev are the two flexible months — one or the other gains or loses a day to keep the festivals from drifting onto the wrong day of the week. That is why an ordinary Hebrew year runs 353, 354, or 355 days.
The month names we use today are not the oldest ones. Seven of the twelve — Nisan, Sivan, Elul, Kislev, Tevet, Shevat, and Adar — entered Hebrew during the Babylonian exile and appear by those names in the later books of Scripture: Esther, Ezra, Nehemiah, and Zechariah.
Three months are named in the Bible only by their older Hebrew names. Iyar is called Ziv, "brightness," when Solomon began building the temple (1 Kings 6:1). Tishrei is Ethanim, the month of the mighty ones, when the ark was brought into that temple (1 Kings 8:2). Cheshvan is Bul, the month of rain, when the building was finished (1 Kings 6:38). Nisan carries an older name too — Abib, "the green ear," the month of the barley harvest and of the Exodus (Exodus 13:4).
Only Tammuz and Av are never named in Scripture at all. The Bible marks them by number alone — "the fourth month," "the fifth month" — which is itself a reminder that the counting came before the names.
The Hebrew calendar keeps two beginnings, and both are biblical.
The sacred year begins with Nisan in the spring, by direct command: "This month shall be unto you the beginning of months: it shall be the first month of the year to you" (Exodus 12:2). Every festival in Scripture is numbered from here — which is why Tishrei, the month of the Day of Atonement, is called the seventh month in Leviticus 23.
The civil year begins with Tishrei in the autumn, at Rosh Hashanah. This is the count used for calendar years, sabbatical years, and the reckoning of reigns.
This is why "the twelfth month" means two different things. In the biblical count it isAdar — Esther says so outright, calling it "the twelfth month, that is, the month Adar" (Esther 3:7). In the civil count the twelfth month is Elul, the month of repentance that closes the year before Rosh Hashanah.
Twelve lunar months run about 354 days — eleven days short of the solar year. Left alone, Passover would drift out of spring within a few years, and the harvest feasts would fall in the wrong season entirely. Scripture ties the feasts to the seasons, so the calendar has to be corrected.
The correction is a thirteenth month. Seven times in every nineteen-year cycle, a leap month is added before Adar. That month is called Adar I (Adar Rishon), and the ordinary Adar becomes Adar II (Adar Sheni). Purim is kept in Adar II, so the festival stays where it belongs relative to Passover a month later. A leap year runs 383, 384, or 385 days.
So the answer to "does the biblical calendar have twelve months or thirteen?" is: twelve named months, and a thirteenth that appears seven years out of nineteen to keep the appointed times appointed.
The Hebrew calendar is God's ancient measure of time — twelve named months that begin with Nisan, the month of the Exodus, and cycle through the feasts, fasts, and seasons of Scripture. Unlike the fixed Gregorian grid, each biblical month follows the rhythm of the moon and gathers its meaning from the events, prayers, and appointed days that fall within it.
Every month on this page carries a Hebrew name, a traditional theme, and sacred signs drawn from Jewish and Christian teaching — tribe, letter, element, and sense. These are not horoscopes or predictions. They are the mazalot framing Scripture uses to mark time: reverent symbols that help you see your birth date within God's story, not apart from it.
Enter your Gregorian birth date below and we will convert it to the biblical calendar — the Hebrew month and day that correspond to the day you were born.
Twelve in an ordinary year, thirteen in a leap year. The thirteenth, Adar I, is added seven times in every nineteen-year cycle to keep the festivals in their seasons.
Twenty-nine or thirty, following the moon. Most months alternate between the two; Cheshvan and Kislev vary from year to year so that an ordinary year comes to 353, 354, or 355 days.
Nisan, in the spring, for the biblical year — "This month shall be the beginning of months" (Exodus 12:2). For the civil year it is Tishrei, in the autumn, at Rosh Hashanah.
Adar, in the biblical count — Esther names it directly as "the twelfth month, that is, the month Adar" (Esther 3:7). In the civil count, which begins at Tishrei, the twelfth month is Elul.
Seven are, by the names we still use: Nisan, Sivan, Elul, Kislev, Tevet, Shevat, and Adar. Three appear under older names — Ziv for Iyar, Ethanim for Tishrei, Bul for Cheshvan — and Nisan is also called Abib. Tammuz and Av are named only by number.
Chodesh (חֹדֶשׁ), from chadash, meaning "new" — a month begins when the new moon is renewed. The plural is chodashim. Scripture also uses the poetic yerach (יֶרַח), from yareach, "moon."
Every one of these months belongs to somebody's birthday. Find yours →