The Perpetual calendar is one of watchmaking’s most exquisitely useful and complex complications, as well as being a traditionally dressy, beautifully finished watch. The mechanism automatically extends February to 29 days once every four years to compensate for the fact that a solar year is actually six hours longer than our 365-day calendar year. A perpetual calendar does this “perpetually,” meaning that the only time it will need adjustment is once every third century. Here is why: Over a period of four centuries, adding a leap day every four years accumulates to about three extra days when compared with actual solar time. The Gregorian calendar therefore omits three leap days every 400 years. Thus, February 29 was deleted in 1700, 1800 and 1900, but not in 2000. For those who like to plan ahead: It will be necessary for you to adjust your perpetual calendar by one day in 2100, 2200 and 2300, but not in 2400.
Chopard L.U.C Perpetual T: This Geneva Seal, COSC-certified movement is a manufacture caliber. The watch is rose gold with a guilloché dial, featuring a large twin-aperture date display, day/night indication and leap-year indicator.
Antoine Martin Perpetual Calendar Grand Balancier : The 85-component rose gold case has detachable strap lugs. Contains a Geneva Seal, in-house caliber, with silicium components and a large balance. Leap year indicator at 12 o’clock and vertical day and month displays.
Patek Philippe 6002G: This Grande Complication is a perpetual calendar, minute repeater with cathedral gongs and a tourbillon, with sidereal time. With blue enameled dial, and hand-engraved case, slide and lugs on white gold.
Rotonde de Cartier Perpetual Calendar Chronograph: In an 18k rose gold case, with in-house self-winding caliber 1904-CH. With sunray guilloché dial, retrograde days at 6 o’clock, month and leap year indicator at 12 o’clock.
A. Lange & Söhne 1815 Rattrapante Perpetual Calendar: With the newly developed caliber L101.1, this is a rattrapante chronograph, perpetual calendar and moonphase display, with a power-reserve indicator. The design is inspired by A. Lange & Söhne classic pocket watches.