At Geneva Watch Days 2025, Greubel Forsey unveiled the Quantième Perpétuel Balancier, a timepiece that condenses one of the maison’s most innovative technical achievements into a form dedicated to clarity and balance. While it is described as a more streamlined version of the QP à Équation launched in 2015, the watch remains a masterwork of horological invention, both historically and mechanically.
Reinventing the Perpetual Calendar
Perpetual calendars have always carried symbolic weight in horology, reconciling the mechanical with the celestial. From Thomas Mudge’s 18th-century experiments to today’s refinements, the complication has remained a proving ground. Greubel Forsey’s system represents the most complete solution to date. When the QP à Équation was launched it redefined what a perpetual calendar watch could be. The choice reflected Greubel Forsey’s philosophy of solving problems through fundamental principles rather than building on existing and known complications.
A diagram of the perpetual calendar “gearbox” that lies at the heart of the Quantième Perpétuel Balancier,
which can be seen on the reverse of the watch to the left of the year indicator
Rather than layering cams and levers horizontally across the movement, Greubel Forsey devised a vertical stack of 25 components in a cam-and-gear configuration. This “mechanical computer” contains all the anomalies of the Gregorian calendar while allowing adjustments forwards and backwards through the crown alone. By eliminating pushers and simplifying corrections, the maison solved one of the longstanding challenges of the complication. By reinterpreting the perpetual calendar, one of horology’s most enduring and intellectual complications, Greubel Forsey demonstrated that there was still new approaches to the problem that would overcome long standing problems.
Distilled Architecture
The new Quantième Perpétuel Balancier presents this ingenuity with heightened legibility. Encased in 45mm of white gold, the movement contains 612 individually finished parts, yet the dial is arranged with deliberate clarity. A large date occupies 3 o’clock, with day and month as a counterbalance at 9 and 12. Leap year and day/night indicators are integrated into the periphery of the dial, and a discreet red arc signals the midnight “danger zone,” safeguarding the mechanism during transitions. The caseback carries the four-digit year display.
The dial side of the Quantième Perpétuel Balancier with the various readouts for date, power reserve, and the inclined balance wheel.
The Inclined Balance
Where the 2015 model employed a 24 second inclined tourbillon, the new edition has a large, inclined balance wheel set at 30 degrees. Designed to minimise positional errors, the balance features a variable-inertia gold mean-time screw. Power comes from twin fast-rotating barrels, delivering a 72-hour reserve.
Greubel Forsey finishing is second to none. The nickel silver bridges are hand-frosted, while steel components have a flawless black polish. Sharp interior angles are cut by file alone, and gold chatons are fixed by blued screws. Each detail reflects the maison’s unique haute horlogerie approach of artisanal craftsmanship and new mechanical invention. Limited series of 22 pieces in white gold. Price: CHF 490,000. Further details, HERE.
Author: Andrew Hildreth
More about Greubel Forsey in their book, The Art of Innovation and in our reviews of their Handmade 2, their Nano Foudroyante EWT Chronograph and the Balancier S among others.
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