24. May 2022

Audemars Piguet Royal Oak Perpetual Calendar Ultra-Thin 26586IP

Ultra-Thin Eye Catcher

Almost three years have passed since the Audemars Piguet Royal Oak Perpetual Calendar Ultra-Thin with reference 26586IP made it into the AP’s official product catalogue. And I think many watch connoisseurs will disagree with me when I say the watch is at least as mesmerizing today as when it was introduced. With a case of 6.3mm in height, it is the world’s thinnest automatic perpetual calendar wristwatch.

You need a lot of expertise in the game of watchmaking, especially when it comes to perpetual calendars. All components must be aligned perfectly with zero room for errors. And the flatter you go, the higher the level of complexity and difficulty. So, no wonder Audemars Piguet put a lot of sweat and effort to build such a masterpiece.

RD#2 Concept

It all started with a concept watch that turned into a reality one year later. As a highlight of the SIHH in 2018, Audemars Piguet introduced the Royal Oak RD#2 Perpetual Calendar Ultra-Thin as a record-breaking automatic QP (ref. 26585PT). The development of the RD#2 took almost five years, which means the prototype’s life began when Francois Henry Bennahmias took over AP’s CEO position. Not a bad move, Mr. FHB.

The main differences between the concept watch of 2018 and the official retail watch are the materials used and the dial structure. While the RD#2 featured the AP’s iconic Tapisserie dial and was entirely made of 950 platinum, the 2019 catalogue piece features a satin-brushed dial and is made of a combination of titanium and 950 platinum.

In-House 5133 Movement

Audemars Piguet R&D Team did an insane job with the new in-house movement 5133. It is just 2.89 mm thick, an almost surreal figure imagining what the mechanism is capable of doing. To reach this remarkable thinness, AP had to re-arrange and merge all three levels of a normal perpetual calendar function into one single layer.

In doing so, Audemars Piguet developed two patented innovations. The end-of-the-month cam has been integrated into the date wheel, while the month cam has been combined with the month wheel. AP is well known amongst watch collectors for its expertise in ultra-thin watch movements, but the 5133 movement is a masterpiece of its own. The new automatic caliber comprises 256 parts and 37 jewels and provides a power reserve of 40 hours when fully wound.

Dial Layout

The Audemars Piguet Royal Oak Perpetual Calendar Ultra-Thin 26586IP features a brushed blue dial with barely-sunken sub-dials. The moonphase is placed atypically at the 12 o’clock position, but it pays homage to AP’s first perpetual calendar launched in 1955. At 3 o’clock, you find the month indicator and the leap year indicator. While the date sub-dial occupies the position of 6 o’clock, the 9 o’clock position features the day indicator, including the day-night indicator—all in all, a dial layout that might be almost too busy for some collectors.

What I miss on the dial is the AP Logo. Although the Audemars Piguet lettering is placed right below the moonphase, I would have liked to find the AP Logo itself somewhere on the dial. Maybe below the lettering? Or perhaps it would ruin the readability of the perpetual calendar completely? We will never know.

Price & Collectability

Although our friends from LeBrassus didn’t put an official limitation on the Audemars Piguet Royal Oak Perpetual Calendar Ultra-Thin 26586IP, you will barely see the watch on someone’s wrist. Thanks to its high complexity, the watch is not easy to produce for AP and is limited to only a few pieces each year. When it was released, the official retail price was at CHF 140,000, while the current market price is around CHF 300,000.



Audemars Piguet


Royal Oak Selfwinding Perpetual Calendar Ultra-Thin (reference 26586IP.OO.1240IP.01)


Official retail price when released was at CHF 140,000, while the current market price is around CHF 300,000.


No official limitation


Diameter: 41 mm; height: 6.3 mm

When to wear:

The watch is a great all-rounder and easy to wear thanks to its lightness and thinness. And a great talking piece among watch lovers. I am sure as soon as a watch enthusiast spots this piece on your wrist, it’s just a matter of time until he joins you for a friendly chat.

What we love about the watch:

We love that the Audemars Piguet Royal Oak Perpetual Calendar Ultra-Thin 26586IP is the thinnest automatic perpetual calendar wristwatch.

Photography: Yves Müller, IG: @wristconspiracy for The Collectors Circle www.thecollectorscircle.com