Widths differ across this line. Enter or pick your exact reference to get its width.
8 to 20 mm
Verification: Not yet verified
Attachment: spring bars or to verify, depending on the reference
39 to 42 mm cases
Indicative information. Check your watch before buying a strap: whatsmylugwidth.com is not responsible for an incorrect size.
The story · Since 2007
In 2007 a house built on rectangles drew a round watch and tucked its blue crown under a metal arch. At its peak that one model made roughly a quarter of Cartier's watch sales.
About 25%
share of Cartier's watch sales the Ballon Bleu reached at its peak, per a senior executive
Cartier presented the Ballon Bleu at the SIHH in 2007, a round case domed on both front and back, with its emblematic crown cap incorporated into the case. To launch it, the house commissioned a comic drawn by seven artists from seven countries under Moebius.
SJX called the Ballon Bleu the most popular Cartier wristwatch of the decade after its launch, citing a senior executive who said it reached roughly a quarter of the brand's watch sales at its peak.
From 2008 a flying tourbillon version existed only in a 46 mm case, driven by the Geneva Seal calibre 9452 MC. In 2014 Cartier brought the same movement into a 39 mm case, with a blue flinqué enamel dial on a white gold edition limited to 100 pieces.
In 2018 Cartier quietly added an entry-level 42 mm steel model with a blue guilloché dial, a colour until then reserved for pricier versions. It ran the in-house calibre 1847 MC and cost only US$250 more than the same watch with an ETA movement.
Just before Watches and Wonders 2021, Cartier added a 40 mm size to the 28, 33, 36 and 42 mm models, with the 1847 MC inside. Its bracelet and strap could now be removed without tools, the bracelet through a proprietary quick-release endlink.
The current range keeps the same case design across sizes: a 28 mm quartz model, a 33 mm automatic on calibre 1853 MC with 37 hours of reserve, and 42 mm automatics on the 1847 MC, all listed with interchangeable bracelets.
She was first pictured with her steel Ballon Bleu on the 2014 tour of Australia; it is widely reported as a third wedding anniversary gift from Prince William. Esquire UK notes she wore it at Wimbledon in 2017 and 2022, and InStyle reports it twice in July 2025.
At the Berlin Film Festival premiere of A Complete Unknown on 14 February 2025 he wore a Ballon Bleu with a pink dial and pink leather strap. He is a Cartier ambassador; GQ reports the watch as worn on the red carpet.
British GQ reports he owns two Ballon Bleu references, one in 18k rose gold and one in white gold with a diamond bezel and moonphase.
The NBCUniversal cable chairman wore a Ballon Bleu to The Hollywood Reporter's Women in Entertainment breakfast.
The Hollywood Reporter lists a Cartier Ballon Bleu among the watches she has been spotted wearing.
Haute Time spotted him wearing a slim Ballon Bleu, which it took for the Extra-Flat in white gold.
2025. Timothée Chalamet took off a pink hoodie on the Berlinale red carpet on 14 February 2025 to reveal a pink-dial Ballon Bleu on a pink strap, a choice British GQ called a surprise.
2014. The then Duchess of Cambridge wore her steel Ballon Bleu during the 2014 royal tour of Australia, the first time she was pictured with it.
2007. Cartier launched the Ballon Bleu with a comic book drawn by seven artists from seven countries, among them Moebius, Jiro Taniguchi, Charles Burns and François Schuiten. Seven, because Cartier has seven letters.
2007. The medium-size Ballon Bleu won the Ladies' Watch Prize at the Grand Prix d'Horlogerie de Genève.
The medium Ballon Bleu won the ladies' category of the GPHG in 2007.
A new size with the 1847 MC, in steel or pink gold, with a silver, blue or grey dial.
40 mm by 12.45 mm; strap and bracelet integrate into the caseband and swap without tools (quick-release endlink for the bracelet, pull-tab spring bars for the strap).
Entry-level 42 mm steel model with a blue flinqué guilloché dial and the in-house 1847 MC.
Same case as the other 42 mm Ballon Bleu, with short lugs.
The tourbillon moved into a smaller 39 mm case; the white gold version had a blue flinqué enamel dial, a first for Cartier's Fine Watchmaking line, in 100 numbered pieces.
A 46 mm pink gold case around the hand-wound 9452 MC, a Geneva Seal movement whose C-shaped carriage shows the seconds.
The 42 mm steel automatic of the launch year, with a silvered guilloché dial, calibre 049 and a date at 3 o'clock.
42.1 mm case, 13 mm thick, sold on a steel bracelet.
Cartier Ballon Bleu references in our database. Each card says where its width comes from: listed by the maker (linked to the maker's page in the details), two independent sources agree, or listed in our database and not yet verified by us.
Ballon Bleu 28 Steel Silver Dial
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 28 mmSilver dialCase material: Steel
Ballon Bleu 33 Pink Gold Diamonds
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 33 mmSilver/ Diamonds dialCase material: Rose Gold
Ballon Bleu 33 Steel Silver Dial
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 33 mmSilver dialCase material: Steel
Ballon Bleu 36 Pink Gold White Roman
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 36 mmSilver dialCase material: Rose Gold
Ballon Bleu 36 Steel Silver Dial
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 36 mmSilver dialCase material: Steel
Ballon Bleu 42 Pink Gold Chocolate Dial
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 42 mmBrown dialCase material: Rose Gold
Ballon Bleu 42 Pink Gold Silver
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 42 mmSilver dialCase material: Rose Gold
Ballon Bleu 42 Steel Black Dial
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 42 mmBlack dialCase material: Steel
Ballon Bleu 42 Steel Blue Dial
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 42 mmBlue dialCase material: Steel
Ballon Bleu 42 Steel Silver Dial
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 42 mmSilver dialCase material: Steel
Ballon Bleu 42 Steel/Gold
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 42 mmSilver dialCase material: Yellow Gold
Ballon Bleu Chronograph 44 Steel
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 44 mmSilver dialCase material: Steel
Ballon Bleu Chronograph Blue
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 44 mmBlue dialCase material: Steel
Ballon Bleu Flying Tourbillon
Lug width: 20 mm
Source: Not yet verified Attachment: Spring barsCase size: 39 mmSilver dialCase material: Platinum
Ballon Bleu Skeleton Dial
Lug width: 20 mm
Source: Not yet verified Attachment: Spring barsCase size: 42 mmSkeleton dialCase material: White Gold
Ballon Bleu XL 46 Steel Silver Dial
Lug width: Integrated bracelet
Source: Not yet verifiedCase size: 46 mmSilver dialCase material: Steel
Ballon Bleu Cartier Ballon Bleu 28mm
Lug width: 8 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 28mm
Lug width: 8 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 28mm
Lug width: 8 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 28mm
Lug width: 8 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 33mm
Lug width: 8.5 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 33mm
Lug width: 8.5 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 33mm
Lug width: 8.5 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 33mm
Lug width: 8.5 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 33mm
Lug width: 8.5 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 33mm
Lug width: 8.5 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 33mm
Lug width: 8.5 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 33mm
Lug width: 8.5 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 36mm
Lug width: 11 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 36mm
Lug width: 11 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 36mm
Lug width: 11 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 36mm
Lug width: 11 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 36mm
Lug width: 11 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 36mm
Lug width: 11 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 36mm
Lug width: 11 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 36mm
Lug width: 11 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 36mm
Lug width: 11 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 36mm
Lug width: 11 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 36mm
Lug width: 11 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 40mm
Lug width: 12 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 40mm
Lug width: 12 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 40mm
Lug width: 12 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 40mm
Lug width: 12 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 42mm
Lug width: 12 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 42mm
Lug width: 12 mm
Source: Not yet verified Attachment: To verifyBallon Bleu Cartier Ballon Bleu 42mm
Lug width: 12 mm
Source: Not yet verified Attachment: To verifyNo reference matches.
Cartier Ballon Bleu references use 8.5 mm or 11 mm or 12 mm depending on the reference and case size, so check yours in the list below. The most common is 11 mm (11 of 32 references with a known width). These widths come from our database and are not yet verified.
No. 5 different lug widths appear across the line, often by case size or generation. Check the reference engraved on the case back or between the lugs.
On the 40 mm introduced in 2021, yes: the bracelet uses a proprietary quick-release endlink and the leather strap pull-tab spring bars. Cartier also lists current 28, 33 and 42 mm models with an interchangeable bracelet.
Before 2021 the core range came in 28, 33, 36 and 42 mm; the 40 mm joined that year. Tourbillon models have used 46 mm and 39 mm cases.
On the 2021 40 mm, the alligator strap comes with a single-fold, twin-trigger deployant clasp, with the strap's tail tucked under the buckle.
The gap between the two lugs that hold the strap, in millimetres. A new strap must match it exactly: 20 mm lugs take a 20 mm strap.
Most watches use spring bars, so any strap of the right width fits. Many smartwatches use their own band system instead, such as Apple Watch bands or Garmin QuickFit.