Birthdays · December

December 18 birthdayZodiac sign, famous birthdays, personality and your 2027 numbers

The short answer

December 18 is a Sagittarius birthday in the third decan of Sagittarius with birthday number 9 and a Personal Year 5 in 2027; Steven Spielberg (1946), Brad Pitt (1963) and Christina Aguilera (1980) were born on December 18 too.

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December 18 zodiac sign: Sagittarius

Sun sign: Sagittarius
Sun at noon UTC: 25.7° to 27.1° Sagittarius
Decan: Third of Sagittarius, 20° to 30°
Element and mode: Fire, mutable
Ruling planet: Jupiter

In every one of the 91 years from 1940 to 2030 the Sun stood in Sagittarius for the whole of December 18, in every time zone on Earth, between 25.7° and 27.1° of the sign at noon UTC, so a December 18 birthday is a Sagittarius birthday whatever the year or the hour.

At noon UTC on December 18 the Sun is in the third decan of Sagittarius, 20° to 30°, in every one of those years, a face that belongs to Saturn in the Chaldean order and is read through Leo, ruled by the Sun, by triplicity; in most years the decan runs from December 12 to December 21, and December 18 is its seventh day.

In most years December 18 is the 27th day of the Sun’s season in Sagittarius, which runs from November 22 to December 21 counted at noon UTC, with three days of it still to come. December 18 is the 352nd day of a common year and the 353rd of a leap year, with 13 days of the year still to come after it.

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Famous December 18 birthdays

The earliest born of the twelve is Christina, Queen of Sweden, in 1626, and the most recent Billie Eilish, in 2001; six of them were born after 1949.

Born since 1950

Brad Pitt (born 1963), American actor
Christina Aguilera (born 1980), American singer, songwriter and actress
Billie Eilish (born 2001), American singer-songwriter
Sia (born 1975), Australian singer and songwriter
Katie Holmes (born 1978), American actress
Ray Liotta (1954–2022), American actor

Born from 1900 to 1949

Steven Spielberg (born 1946), American filmmaker
Keith Richards (born 1943), British musician, guitarist of the Rolling Stones

Born in the 1800s

J. J. Thomson (1856–1940), British physicist
Archduke Franz Ferdinand of Austria (1863–1914), heir presumptive to the throne of Austria-Hungary
Paul Klee (1879–1940), German-Swiss artist

Born before 1800

Christina, Queen of Sweden (1626–1689), Queen of Sweden, ruled from 1632 until abdication

Birthdays from Wikidata, checked against Wikipedia’s “On this day” births: the twelve best known of the 70 people the Almanac’s table keeps for December 18, by how many Wikipedia editions cover them, with dates before the calendar reform as the sources give them.

December 18 birthday personality

Saturn rules the last face of Sagittarius in the Chaldean scheme while Leo lends the Sun’s confidence, so belief is read here as conviction that has been tested: the teacher, the elder, the one whose principles have cost them something. Tradition warns against a certainty that stops listening.

Born on the 18th, 1 and 8 add to 9: the leader and the steward together, finishing in compassion. Numerology reads it as a birthday with a wide horizon and strong convictions. With fire, the 9 is read as idealism with energy, a generosity that wants to change things rather than only feel for them.

A question to carry from December 18: which chapter of your life is your hope ready to close with thanks?

The Sun in Sagittarius and the number 9 are only part of the story: your Moon, your rising sign and the rest of your chart have as much to say, and the tradition offers all this as a mirror, never a verdict.

Birthday number 9

Born on the 18th, 1 + 8 = 9, so your birthday number is 9: a 9 vibration supports completion, compassion, release, wisdom, and humanitarian energy, with compassion and wise completion as its gift and martyrdom, heavy endings, or emotional overextension as its strain.

Your 2027 numbers

Pythagoras with a small lyre, pointing to a triangle of ten pebbles in his palm, an engraving — Pythagoras, the philosopher of number

For a birthday on December 18 the house method reduces the birth month and the day on their own and adds the Universal Year of 2027, 11 (2 + 0 + 2 + 7 = 11, a master number kept whole), as it stands: December, the 12th month, reduces to 3, the 18th reduces to 9, and 3 + 9 + 11 = 23, which reduces to 5, so 2027 is your Personal Year 5.

A Personal Year 5 is read as a year of change and movement, of travel, new people and loosened routines. Beside the Universal Year 11 it is read as change guided by intuition rather than restlessness.

Personal Months of 2027, a Personal Year 5: Jan 6 Feb 7 Mar 8 Apr 9 May 1 Jun 11 Jul 3 Aug 4 Sep 5 Oct 6 Nov 7 Dec 8

In 2027 December 18 falls on a Saturday, the day the old reckoning gives to Saturn, and is a Personal Day 8 (8 + 18 = 26, then 8) in a Personal Month 8 (5 + 12 = 17, then 8), while June is a master month 11; the Personal Year itself turns on 1 January, not on the birthday.

December birthstone and birth flower

Birthstones: Turquoise, tanzanite and zircon
Birth flowers: Narcissus, and holly as the second flower

December’s turquoise, tanzanite and zircon come from the modern list (the Jewelers of America list of 1912, as since revised), and its narcissus and holly from The Old Farmer’s Almanac.

More birthdays

Common questions

What zodiac sign is December 18?

Sagittarius: from 1940 to 2030 the Sun stayed in Sagittarius for the whole of December 18 in every year and every time zone, 25.7° to 27.1° into the sign at noon UTC, so no birth year or birth time changes it.

Is December 18 a cusp birthday?

No: the Sun stays in Sagittarius all day on December 18 in every year from 1940 to 2030, wherever on Earth the birth takes place, and the nearest cusp birthday is December 21, three days later.

Who was born on December 18?

Among the best known people born on December 18 are Steven Spielberg (born 1946), Brad Pitt (born 1963) and Christina Aguilera (born 1980), with Billie Eilish, J. J. Thomson and Archduke Franz Ferdinand of Austria and six more named on this page.

What is the birthday number for December 18?

9. Born on the 18th, 1 + 8 = 9, so your birthday number is 9: a 9 vibration supports completion, compassion, release, wisdom, and humanitarian energy, with compassion and wise completion as its gift and martyrdom, heavy endings, or emotional overextension as its strain.

What is the 2027 Personal Year for a December 18 birthday?

5. For a birthday on December 18 the house method reduces the birth month and the day on their own and adds the Universal Year of 2027, 11 (2 + 0 + 2 + 7 = 11, a master number kept whole), as it stands: December, the 12th month, reduces to 3, the 18th reduces to 9, and 3 + 9 + 11 = 23, which reduces to 5, so 2027 is your Personal Year 5.