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Sienna Miller

Photo: Martin Kraft, CC BY-SA 3.0, via Wikimedia Commons

Actor

Sienna Miller

British-American actress (born 1981)

Sienna Miller is 44 years old, born on December 28, 1981 in New York City.

Next birthday in 54 days, turning 45.

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Born
December 28, 1981, New York City
Age
44
Zodiac sign
Capricorn
Country
United Kingdom, United States
Known as
Actor

Official links: Instagram · Wikipedia

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Sienna’s birthday, by the numbers

  • Sienna Miller was born on a Monday.
  • Sienna Miller has been alive for about 16,382 days.
  • Their 20,000-day milestone falls on September 30, 2036.
  • Their next birthday, turning 45, is on a Monday.
  • Next milestone: Sienna Miller turns 50 on December 28, 2031, in 5 years and 1 month. More milestone birthdays
  • Sienna Miller is younger than 4,100 and older than 2,746 of the living celebrities on CFOTD.
  • Half birthday: June 28. Birthstone: Turquoise, tanzanite and zircon.
  • Sienna Miller belongs to Millennials.

Age gaps

Born within weeks of Sienna

Britney SpearsSinger · December 2, 1981Xabi AlonsoSoccer player · November 25, 1981David VillaSoccer player · December 3, 1981Dima BilanSinger · December 24, 1981Dwyane WadeBasketball player · January 17, 1982Amy LeeSinger · December 13, 1981

Days and weekdays are worked out from the birth date. Compare Sienna’s age with anyone.

Share Sienna Miller’s birthday, December 28?Make something for yourself or a birthday friend.
🏅Birthday certificateAdd a name, download a PDF or image🎂Printable birthday pageA free one-page PDF for December 28⭐Birthday twin cardA square card to share

Also born on December 28

All →
John LegendSinger · Age 47Richard ClaydermanMusician · Age 72Salvador SobralSinger · Age 36KaliopiSinger · Age 59Seth MeyersComedian · Age 52Noomi RapaceActor · Age 46

Also born in 1981

All →
Britney SpearsSinger · December 2Zlatan IbrahimovićSoccer player · October 3Serena WilliamsTennis player · September 26Paris HiltonTV host · February 17Chris EvansActor · June 13Iker CasillasSoccer player · May 20

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Birth dates and details from Wikidata (checked October 15, 2026, newest names added October 27, 2026). Ages update every day. Photos are freely licensed and credited on each profile. How we build this site · Report a mistake

Frequently asked questions

How old is Sienna Miller?

Sienna Miller is 44 years old, born on December 28, 1981 in New York City.

What is Sienna Miller’s zodiac sign?

Capricorn, born December 28.