How To Read Audemars Piguet Reference Numbers
The complete reference number of an AP watch not only tells you the specific model (for example a Royal Oak or a Millenary) but also includes material, collection, and dial codes.
An Audemars Piguet reference number is typically structured like this:
#####XX.XX.####XX.##
where # represents a number and X represents a letter.
For example, 15400ST.OO.1220ST.02.
The first numbers are the model number. Here are some common examples:
15500 - Royal Oak Selfwinding 41mm
15550 - Royal Oak Selfwinding 37mm
77350 - Royal Oak Selfwinding 34mm
16202 - Royal Oak "Jumbo" Extra-Thin 39m
26715 - Royal Oak Selfwinding Chronograph 38mm
26240 - Royal Oak Selfwinding Chronograph 41mm
26420 - Royal Oak Offshore Selfwinding Chronograph 43mm
26238 - Royal Oak Offshore Selfwinding Chronograph 42mm
26231 - Royal Oak Offshore Selfwinding Chronograph 37mm
These are followed by letters that denote the case material. The most common letters you’ll find in Audemars Piguet reference numbers are as follows:
BA – Yellow Gold
BC – White Gold
CB – White Ceramic
CE – Black Ceramic
IO – Titanium and Ceramic
OR – Rose Gold
PT – Platinum
RO – Rose Gold and Ceramic
SA – Steel and Yellow Gold
SO – Steel and Ceramic
SR – Steel and Rose Gold
ST – Stainless Steel
TI – Titanium
The next pair of letters in the AP reference number is the bezel code. The most common bezel codes in Audemars Piguet reference numbers are as follows:
OO – Smooth Bezel
ZZ – Diamond-Set Bezel
YG/YY – Colored Gemstone-Set Bezel
GG – Frosted (Hammered) Gold Bezel
The following set of numbers and letters is the bracelet and/or strap code. Again, the letters denote the material of the bracelet, which in many instances matches the case material letters. However, there are a few additional non-metal bracelet material abbreviations to know:
CA – Rubber Strap
CR – Leather Strap
KB – Rubber-Coated Strap
VE – Calfskin Strap
Finally, the last two numbers in an Audemars Piguet reference number is a dial code, which is different for each model.
While the entire AP reference number is composed of 17 digits, each model is often referred to only by the first set of alphanumeric codes. For example, ref. 15400ST, ref. 26420SO, and ref. 15210BC.
I've worked in different areas of the watch industry over the last 15 years. Now, I'm a freelance luxury watch writer. Instagram @luxwatchwriter. Champion of #ladieswhocrunch.
As always thanks for the informative rundown @celinesimon. A lot of folks want to crap on AP for having "one "watch. Others do not consider them part of the "Holy Trilogy" as a result. Meanwhile, the watch that came up on three of four threads here, the new super-thin RM, is made possible because of the AP movement inside of it. Not enough knowledge of the history of the brand to truly appreciate all they do for the industry. Kudos on moving folks a step further in their knowledge.
As always thanks for the informative rundown @celinesimon. A lot of folks want to crap on AP for having "one "watch. Others do not consider them part of the "Holy Trilogy" as a result. Meanwhile, the watch that came up on three of four threads here, the new super-thin RM, is made possible because of the AP movement inside of it. Not enough knowledge of the history of the brand to truly appreciate all they do for the industry. Kudos on moving folks a step further in their knowledge.
Thanks @AllTheWatches! I have great respect for AP and its history - it definitely belongs in the Trinity.
As for the “one watch” argument, what people seem to forget is that there are countless variations of the RO (and ROO), ranging from time only and chronograph to perpetual calendar and minute repeater. Just because it’s the same base shape doesn’t make the variation any less impressive. All modern Rolex watches (except for the Cellini) are some variation of the Oyster Perpetual, after all. 😃
thx for the insight @celinesimon appreciated it 🙏🏻
thx for the insight @celinesimon appreciated it 🙏🏻
You're welcome! I enjoy writing these :)
Thx. Celine. Hope your head is recovering from the decrypting session.
Thx. Celine. Hope your head is recovering from the decrypting session.
My husband thinks I'm really weird because I'm always blurting out reference numbers and random codes 🤣
I think this is a common issue. My wife thinks I'm weird as well for similar reasons. But she has learnt to deal with it. When I talk about watches she is very polite and very patient with me. 😀
My husband thinks I'm really weird because I'm always blurting out reference numbers and random codes 🤣
Thank you so much for putting this together Celine. 👏 I love geeking out on this kind of thing and I really really hope I'm in a position one day where I have to check the reference number of the AP I'm buying 😁
Thank you so much for putting this together Celine. 👏 I love geeking out on this kind of thing and I really really hope I'm in a position one day where I have to check the reference number of the AP I'm buying 😁
I think a ref. 15550ST.OO.1356ST.02 would look lovely on you!
Wow! That’s good information as always 👍. Thank you for sharing. 🍻
Wow! That’s good information as always 👍. Thank you for sharing. 🍻
Thank you!
I miss content like this…
Thanks for sharing. There’s a science other madness. Like Rolex model numbers Audemars also follow a distinct pattern🇨🇭🇨🇭