or centuries, the perpetual calendar has been revered as one of watchmaking’s most prestigious complications. Yet it often came with compromises: fragile mechanisms, cryptic interfaces and laborious resets whenever the watch stopped. Greubel Forsey set out to change that.

In 2015 the QP à Équation introduced the Mechanical Computer – the brand’s seventh Fundamental Invention – a 25-part mechanical brain that “knows” the Gregorian calendar rules, ensuring perfect synchronisation of every display. The new QP Balancier distills this breakthrough into its most refined form. It unites 12 indications – hours, minutes, seconds, power reserve, day, date, month, leap year, day/night, 24-hour display, calendar year and the patented function selector – all operated by a single crown for effortless time and calendar setting.

Powered by the patented Mechanical Computer and multiple security systems, the perpetual calendar at the heart of Greubel Forsey’s QP Balancier adjusts instantly in either direction, restarts instantly after months unwound, and stays programmed until the year 2100. Featuring the brand’s 30° inclined balance wheel, it is limited to 22 timepieces in white gold.

Every limitation of traditional perpetual calendars has been eliminated. The QP Balancier turns freely in both directions at any time of day, corrects instantly even after months unwound, and locks safely during the vulnerable midnight changeover, with a visible red zone for extra security. Programmed correctly until February 28, 2100, it needs only a simple Atelier adjustment to remain accurate for another century.

The 45.1mm white gold case, just 14.75mm high, houses the 12.6mm balance wheel inclined at 30°, a high-mass, variable-inertia balance with gold mean-time screws for superior chronometric performance. Each of its 612 components is hand-finished to the Atelier’s uncompromising standards – bevelled, black-polished, frosted or straight-grained – with twin fast-rotating barrels delivering a 72-hour chronometric power reserve.

Price on request

www.greubelforsey.com