Complication
Perpetual Calendar
Knows the date, month, and leap years — until 2100.
What it does
A perpetual calendar tracks the date, day, month, and the four-year leap cycle mechanically, automatically accounting for 28-, 30-, and 31-day months. A correctly-set QP won't need a date correction until the year 2100 (a non-leap-year exception in the Gregorian calendar).
How to read it
Sub-dials and windows show day, date, month, and often the leap-year position and moonphase. Keep it wound — if it stops, resetting all the indications is a delicate, sometimes dealer-only, job.
Impact on value
Strongly positive — one of the classic 'grand complications' and a major driver of value.
Keep reading
- Complication
Tourbillon
A rotating cage that averages out gravity's error.
- Complication
World Time
All 24 time zones readable at once.
- Complication
Annual Calendar
Knows every month length except February.
- Complication
Alarm
A mechanical buzzer on your wrist.
- Complication
Minute Repeater
Chimes the time on demand, to the minute.
- Complication
Small Seconds
A seconds hand on its own sub-dial.