Audemars Piguet Perpetual Calendar with Calibre 7138
To mark the beginning of its 150th anniversary celebrations, Audemars Piguet presents a new generation of self-winding perpetual calendar movement, Calibre 7138, which for the first time ever, enhances user comfort by making the corrections of all functions possible via its “all-in-one” crown.
This new movement makes its debut on a 41 mm Code 11.59 by Audemars Piguet in 18-carat white gold, on two 41 mm Royal Oak models in a choice of stainless steel or 18-carat sand gold, and on three corresponding “anniversary” limited editions of 150 pieces, each featuring subtle aesthetic details that pay homage to the Manufacture’s 150 years of uncompromising craftsmanship.
Five years of development went into the creation of this horological feat, which is protected by five patents and offers new creative horizons.
Perpetual calendar, one of the most complex calendar watches in existence today, has a mechanical memory capable of mapping 48-month time cycles, automatically adjusting the varying number of days in each month, even during leap years. This complex mechanism requires manual intervention only once every 100 years to keep it in sync with our solar time.
This manual adjustment serves to compensate for the difference between the solar year (based on the time it takes the Earth to orbit the Sun, which is 365,2421875 days) and the civil year (based on our Gregorian calendar of 365 days).
To make up for this discrepancy, which slowly builds up over the years, the Gregorian calendar adds an extra day in February every 4 years (leap year) and omits the leap year in centurial years that are not divisible by 400. Although programmed to adjust the varying number of days in each month, even in leap years, the perpetual calendar does not automatically remove leap years in centurial years not divisible by 400.
Building on its heritage and past developments while looking to the future, Audemars Piguet has reimagined the perpetual calendar mechanism with ergonomics in mind to adapt this classic complication to an ever-more flexible lifestyle.
Traditional perpetual calendar wristwatches are usually equipped with correctors inserted in the side of the case, which are activated by using a small tool to adjust the various subdials. This age-old system can make it cumbersome to set the watch, especially when left unwound for some time.
To enhance user’s experience and streamline the design of the case, AP’s engineers have developed an easier and more intuitive correction system entirely controlled via the crown, to make this high complication adjustable anywhere without tools and without risk of damage.
The new crown incorporates four different positions. The first enables to wind the watch clockwise. Pulling the crown out one step (position 2) allows to set the date clockwise and to adjust the month and the leap year in the opposite direction. By pulling the crown out again (position 3), the user can set the time bidirectionally. The last position is reached by pushing the crown back one step (position 2’) to set the day and week clockwise and the moon phases counter-clockwise.
The simplicity of the new crown correction conceals, however, a complex mechanism driven by an innovative lever and wandering wheels system that meshes with the different calendar wheels in the 2 and 2’ positions. This innovation is protected by two patents: one for the crown correction system with a 2’ position and one for the month and date correction via the crown.
The new crown correction system has enabled the Audemars Piguet teams to eliminate the correctors on the side of the case and streamline the design of the new perpetual calendar models.
As all calendar functions are synchronised thanks to the new crown correction system and more robust movement construction, it is impossible to desynchronise the watch and damage the mechanism if the user tries to set their watch when the automatic date change mechanism is active (between 9 pm and 3 am).
The dial and subdials have been rearranged to enhance legibility, symmetry and aesthetic harmony. The dial now features a European date display, with the day at 9 o’clock, the date at 12 and the month at 3 o’clock.
The week numbers are printed on the inner bezel as for previous perpetual calendar models. However, it is now the first week of the year (“1”) that appears at 12 o’clock (instead of week 52). In the same logic, “Monday” and “1” have been aligned at 12 o’clock in their respective subdial to mark the start of the week and the first day of the month.
The dial also features a patented progressive step for the date display at 12 o’clock. The AP teams developed a date wheel with 31 custom-made teeth, the size of which varies to adapt to the width of the digits and enhance readability.
To achieve perfect symmetry with the subdial at 3 o’clock, which indicates the month and leap year, a 24-hour indicator has been inserted in the day subdial at 9 o’clock. In addition, a no-correction zone is marked in red between 21 h and 3 h to show when the watch cannot be set. However, if the user attempts to set the watch during this time, the date might not be corrected, but there is no risk of damaging the movement in the process.
The moon phase, which displays a realistic depiction of the moon based on a NASA photograph, remains at 6 o’clock as for previous references. However, the full moon is now centred on the 12 o’clock axis to strengthen the dial’s overall harmony.
The subdials have been rearranged and optimised to improve legibility and to display the date in the European format (day, date, month) when reading the dial from left to right.
Audemars Piguet’s new in-house perpetual calendar movement combines state-of-the-art R&D technology with age-old horological expertise.
Calibre 7138 automatically takes into account the number of days in the month and correctly displays the date and week even in leap years. Assuming the watch is kept fully wound, the date will not require manual correction until the year 2100, when it will need to be adjusted to stay in line with the Gregorian calendar.
With selfwinding Calibre 7121 as its base, it beats at a frequency of 4 Hz (28,800 vph) and offers a power reserve of minimum 55 hours.
Calibre 7138 also builds on the patented innovations of Calibre 5133 launched in 2018 with the Royal Oak Selfwinding Perpetual Calendar Ultra-Thin RD#2, which incorporated all perpetual calendar functions in one single layer within the movement.
The end-of-month cam is similarly integrated with the date wheel, while the month cam is combined with the month wheel. Crown corrections form a second layer, enabling the movement to keep a thin 4.1 mm profile. Calibre 7138 is decorated with refined Haute Horlogerie decorations, including Côtes de Genève, satin-brushing, circular graining and satin, snailing as well as chamfering, all visible on the caseback side.
Calibre 7138 incorporates multiple patented innovations for its crown correction, progressive date display and ultra-thin construction based on the breakthroughs of Calibre 5133 (RD#2).
The Gregorian calendar omits three leap years every 400 years to keep in sync with solar time. This is achieved by omitting the 29th February in the century years that are divisible by 100, but not by 400. As a result, 2100 will not be a leap year and perpetual calendar mechanisms will have to be moved forward by one day.
Calibre 7138 makes its debut with one Code 11.59 by Audemars Piguet and two Royal Oak models, all available in 41 mm. The absence of correctors on the side of the case reinforces the refinement of the three models as well as their water resistance, which has been increased to 50 m for the Royal Oak models and 30 m for the Code 11.59 by Audemars Piguet compared to the previous perpetual calendar models offered in the two collections (20 m).
The new 41 mm Code 11.59 by Audemars Piguet timepiece continues the collection’s seamless blend of technical modernity and ancestral craftsmanship. It features an 18-carat white gold case, whose multi-layered architecture is highlighted by the Manufacture’s alternation of satin- brushing and polished chamfers that play with the light.
It is enhanced by the collection’s signature embossed dial in smoked blue PVD shades. The pattern is made up of concentric circles that ripple outwards from the centre of the dial and is decorated with hundreds of tiny holes that give it light, depth and character.
This motif, which made its debut in the collection in 2023, was created in collaboration with Swiss guilloché artisan Yann von Kaenel, who hand-engraved the basic stamps. The dial is complemented by 18-carat white gold luminescent hands, white gold hour-markers and white calendar indications for an elegant two-tone design. The timepiece is fitted on a blue rubber-coated strap with calfskin lining matching the hue of the dial, decorated with a textile motif for a contemporary twist.
The new Code 11.59 by Audemars Piguet model presents a refined two-tone aesthetic with its 18-carat white gold case, smoked blue dial and matching rubber-coated strap.
The first Royal Oak model also offers a two-tone aesthetic. It combines a stainless steel case and bracelet with a blue PVD Grande Tapisserie dial with matching subdials and inner bezel. The dial is enhanced by 18-carat white gold hands and hour-markers, all filled with luminescent material. White calendar indications on the inner bezel and subdials add the finishing touch.
The second Royal Oak timepiece presents a contemporary monochrome aesthetic with unique light effects. The case and bracelet are crafted in 18-carat sand gold, a precious alloy combining gold with copper and palladium, introduced in the Royal Oak collection in 2024.
Hovering between white and pink gold, its colour changes according to the light, giving it a warm appearance. The Manufacture’s trademark satin-finishing and polished chamfers on the bracelet and case accentuate the material’s chromatic variation.
The timepiece is adorned with a Grande Tapisserie dial, subdials and inner bezel, all in the same sand gold shade, obtained by galvanic treatment. The 18-carat white gold hands and hour-markers with luminescent material add a touch of refinement, while the black calendar indications printed on the subdials and inner bezel provide a subtle contrast. The three models have a sapphire caseback that reveals the refined aesthetic of Calibre 7138.
The open-worked 22-carat pink gold oscillating weight and the barrel bridge visible from 12 to 3 o’clock stand out against the other rhodium-toned components of the movement.
To celebrate the Manufacture’s 150 years, the three models presented above are also available in a limited “anniversary” edition of 150 pieces each. While their aesthetics are identical to those of the collection models, the three limited editions feature subtle design codes specially conceived for the celebration.
These include a vintage “Audemars Piguet” signature inspired by historical documents, inserted in the moon- phase subdial at 6 o’clock. The three limited editions also incorporate two additional engravings on the sapphire caseback frame: the “150” logo, created for the occasion, and “1 of 150 pieces.”
History of Audemars Piguet Perpetual Calendar Watches
Astronomical watches are deeply rooted in the Vallée de Joux’s watchmaking legacy, as watchmakers have always drawn inspiration from the region’s clear night sky. Audemars Piguet’s uninterrupted history of astronomical complications started with the two founders’ school pocket watches, both completed around 1875.
The one attributed to Jules Louis Audemars, which combined a perpetual calendar with a quarter repeater mechanism and a rare independent deadbeat seconds, saw several evolutions at the company’s workbenches over the following twenty years. Yet, during the company’s first two decades, calendar complications accounted for less than 10% of its total production. Its first complete calendar wristwatch was put into production in 1921 and sold three years later to the renowned retailer Gübelin.
From 1921 to 1970, 188 complete calendar wristwatches were produced – a small part of the Manufacture’s total production during these years. In 1955, the company released the world’s first perpetual calendar wristwatch with leap year indication, nine examples of which were created between 1955 and 1957.
The result of a collaboration between Audemars Piguet, LeCoultre & Cie and Vacheron Constantin, Calibre 2120 was produced and perfected for over 50 years.
The brand broke another record in 1978 at the height of the quartz crisis with the world’s thinnest selfwinding perpetual calendar wristwatch of its time, Calibre 2120/2800. Conceived in secret by three watchmakers, this ground-breaking perpetual calendar movement achieved its extra-thinness (3.95 mm) by using the ultra-thin Calibre 2120 (2.45 mm thick), launched in 1967, as its base. Over the next 18 years, more than 7,000 movements were produced, cased and sold, ushering in a new era of growth for the brand and paving the way for the revival of classical complications.
In 1984, this calibre powered the first Royal Oak Perpetual Calendar (39 mm in diameter), Model 5554, soon followed by other references in the collection.
AP released the first perpetual calendar wristwatch with leap year indication (Model 5516) in 1955, followed in 1978 by the thinnest perpetual calendar of its time.
Launched in 2015, Calibre 5134 adapted the perpetual calendar movement to a larger 41 mm case diameter, while maintaining a thin profile of 4.3 mm. It was first housed in a new Royal Oak perpetual calendar model with a dynamic aesthetic, bringing renewed attention to this classic complication, which had been in decline since the end of the 20th century. This revival was confirmed in 2017 with the release of the Royal Oak Perpetual Calendar 26579CE in black ceramic, which caused a sensation.
This calibre powered numerous perpetual calendar wristwatches across the Manufacture’s collection until 2024, when it retired. It was last featured on the Royal Oak Perpetual Calendar “John Mayer” Limited Edition, bringing down the curtain on a story that began in 1978.
In 2018, the Manufacture opened yet another chapter in its history of perpetual calendar timepieces with the launch of the revolutionary 41 mm Royal Oak Selfwinding Perpetual Calendar Ultra-Thin, known as RD#2 – the world’s thinnest automatic perpetual calendar wristwatch of its time.
This 6.3 mm-thick watch houses Calibre 5133, an ultra-thin movement measuring just 2.89 mm in height, which was fully redesigned to incorporate all the perpetual calendar functions on one single level, heralding a new generation of astronomical watches.
Building on the patented inventions that made RD#2 possible, Calibre 7138 pushes the limits of feasibility once more by offering an intuitive, user-friendly complication that can be set and corrected anywhere, without tools.
Perpetual Calendar wristwatches have never stopped evolving at Audemars Piguet. The Royal Oak Selfwinding Perpetual Calendar Ultra-Thin (RD#2) broke another record in 2018 with its calendar functions reengineered on one single plane.
The Royal Oak Perpetual Calendar “John Mayer” Limited Edition bid goodbye to Calibre 5134 in 2024, paving the way for a new generation of ergonomic complications.
Audemars Piguet Perpetual Calendar with Calibre 7138
Movement
Selfwinding Calibre 7138
Total diameter 29.6 mm (12 ¾ lignes)
Total thickness 4.1 mm
Number of parts 422
Number of jewels 41
Minimum power reserve guaranteed 55 h
Frequency of balance wheel 4 Hz (28,800 vibrations/hour)
Functions
Perpetual calendar with week indication, day, date, astronomical moon, month, leap year, hours and minutes
Code 11.59 by Audemars Piguet Selfwinding Perpetual Calendar 41 mm, Reference 26494BC.OO.D350KB.01
Case
18-carat white gold case
Double curved glare-proofed sapphire crystal
White gold and glare-proofed sapphire caseback
Water-resistant to 30 m
Case thickness: 10.6 mm
Dial
Smoked blue Code 11.59 by Audemars Piguet embossed signature dial
Blue sub-dials
18-carat white gold hour-markers
18-carat white gold hands with luminescent material
Blue snailed inner bezel
Strap
Blue textured rubber strap with calfskin lining, 18-carat white gold three-blade folding clasp
Limited edition
To celebrate Audemars Piguet’s 150th anniversary, a special “anniversary” limited edition of the 41 mm Code 11.59 by Audemars Piguet Selfwinding Perpetual Calendar has been created. Limited to 150 pieces, it features subtle design codes conceived for the occasion (ref. 26494BC.OO.D350KB.02).
Audemars Piguet Royal Oak Selfwinding Perpetual Calendar 41 mm, Reference 26674ST.OO.1320ST.01
Case
Stainless steel case
Glare-proofed sapphire crystal and caseback
Water-resistant to 50 m
Case thickness: 9.5 mm
Dial
Blue dial with Grande Tapisserie pattern
Blue subdials
18-carat white gold hour-markers and Royal Oak hands with luminescent material
Blue inner bezel
Bracelet
Stainless steel bracelet with AP folding clasp
Limited Edition
To celebrate Audemars Piguet’s 150th anniversary, a special “anniversary” limited edition of the 41 mm Royal Oak Selfwinding Perpetual Calendar has been created. Limited to 150 pieces, it features subtle design codes conceived for the occasion (ref. 26674ST.OO.1320ST.02).
Audemars Piguet Royal Oak Selfwinding Perpetual Calendar 41 mm, Reference 26674SG.OO.1320SG.01
Case
18-carat sand gold case
Glare-proofed sapphire crystal and caseback
Water-resistant to 50 m
Case thickness: 9.5 mm
Dial
Sand gold-toned dial with Grande Tapisserie pattern
Sand gold-toned subdials
18-carat white gold hour-markers and Royal Oak hands with luminescent material
Sand gold-toned inner bezel
Bracelet
18-carat sand gold bracelet with AP folding clasp
Limited Edition
To celebrate Audemars Piguet’s 150th anniversary, a special “anniversary” limited edition of the 41 mm Royal Oak Selfwinding Perpetual Calendar has been created. Limited to 150 pieces, it features subtle design codes conceived for the occasion (ref. 26674SG.OO.1320SG.02).
