A perpetual calendar, also known as quantième perpétuel, is one of the most complex watch complications.
They don't just tell time but also automatically adjust for varying month lengths, including leap years and February. Plus, they display the moon phase accurately. Most shockingly, they don't need to be adjusted until the year 2100!
Still curious to learn more about them? Here's everything you need to know about their history, how they work, and our top 5 picks.
What Is a Perpetual Calendar Watch?
A perpetual calendar is made to keep track of the day, date, and year accurately until 2100. It adjusts for leap years, the 28-day February, and the different lengths of months. It also shows the current year, moon phases, and whether it's a leap year.
The oldest perpetual calendar pocket watch was created in 1762 by Thomas Mudge. One was sold at Sotheby's auction, and another is still at the British Museum. Before Patek Philippe patented the annual calendar, they patented a mechanism for a perpetual calendar in 1889 for use in pocket watches.
Making one of these watches is quite a task! It needs about 200 extra parts and takes months to put together.
How Does a Perpetual Calendar Watch Work?
The perpetual calendar movement has a mechanical memory of four years, which is 1,461 days. There are multiple variations of this watch, but in general, a wheel turns every four years to align the calendar accurately with the length of each month.
Most of these watches have different parts for each section of the calendar. These parts are synced up by a long lever called the Grand Lever. It stretches across the top of the watch and goes through the middle of the hands.
Then, it directs the aperture (a special wheel with bumps and grooves) depending on whether the month has 28, 30, or 31 days or if it's a leap February with 29 days. As the date changes, the Grand Lever moves back and forth to send information to the right parts of the clock.
Annual vs. Perpetual Calendar Watches
Annual calendar watches are often confused with perpetual ones. In reality, they're two ends of the calendar watch spectrum. The main difference is whether it needs manual resetting each year.
Let's look at a few other differences.
Annual Calendar
- Needs adjustment at the end of February.
- Introduced in 1996.
- Affordable
Perpetual Calendar
- Doesn't need adjustment until the year 2100.
- Introduced in 1925.
- Expensive.
History of Perpetual Calendar Watches
In 1762, Thomas Mudge created the original perpetual calendar pocket watch, which now resides in the British Museum.
Patek Philippe developed their own version about a century later. However, it took them 25 more years to patent this complex mechanism. They created the first compact perpetual calendar movement for a pendant watch designed for women.
This movement used various parts – a wheel, a heartpiece, and levers – working together to rotate the star wheels. In 1925, Patek Philippe used this mechanism to create the first perpetual calendar wristwatch, commissioned by a collector. It took two years to complete.
In 1934, Breguet introduced its "Ref. 4244 Instantaneous" perpetual calendar wristwatch. Although Philippe did it first, some consider Breguet's the first true perpetual calendar wristwatch. That's because Patek Philippe used a converted pocket watch movement.
Meanwhile, Breguet's Ref. 4244 had about 100 moving parts and an instantaneous 'jump' system to boost all calendar functions at the same time. It was acquired by Mr. Dollfus in 1934 for 11,000 Swiss Franc and later sold at a Christie's auction in 2011 for $475,618.
Patek Philippe is still a leader in this field and is known for its perpetual calendar chronographs.
Problems With The Perpetual Calendar Watch
Perpetual complications are added onto a basic watch movement; they're not an independent type of watch. Here's the issue: they can really affect the watch's appearance.
When the Grand Lever moves back and forth, it signals the watch when to change the date. This takes up space inside the watch and limits how the day and date can be shown – usually through little windows – which often means the face has to be bigger.
Another issue is that sometimes the perpetual calendar might miss a day when you try to change the date. Most of these calendars are set up for a default 31-day month, so they have to skip through extra days for shorter months and even up to 47 days for leap years. This is where errors can happen.
Plus, if you try to change the date while the watch is still in the middle of changing it by itself, you could end up damaging the mechanism.
To avoid these problems, it's a good idea to set your perpetual calendar when the clock hands show 9 in the morning. At this time, nothing inside the watch is changing, so it's safer to adjust it.
The time to avoid is between 5 PM and 2 AM when the moon phase starts moving. The other parts of the watch start changing the most around midnight.
5 Best Perpetual Calendar Watches
With all the knowledge you have about this complication, you can start your journey of finding the best perpetual calendar watch. Here are our top 5 picks to get you started.
Jaeger-LeCoultre Master Perpetual Calendar
The JLC Master Perpetual takes the calendar to the next level. It has three smaller dials and shows the moon phase, but it's still easy to read and looks well-balanced.
You can see the month and year at the very top, and, at 3 o'clock, you'll find the day of the week. At 6 o'clock, there's the 29 ½ day moon phase, and at 9 o'clock, you'll see the date.
You can adjust the day, date, and month using the button at 8 o'clock, but it doesn't allow you to set it to a wrong combination of dates.
A Lange & Sohne Datograph Perpetual
The Datograph Perpetual by A. Lange & Sohne is a watch that's easy to fall for.
Its 41mm case holds both a perpetual calendar and a flyback chronograph. The date is shown prominently in a large window at 12 o'clock, and you can activate it with the button at 10 o'clock.
You can't accidentally change the date on this watch; you'll need to pull out the crown to adjust it along with the day of the week at 9 o'clock. The month is displayed at 3 o'clock along with the 30-minute timer.
Lastly, the leap year indicator sits just below the month display, and the moon phase is at 6 o'clock on the dial.
Patek Philippe Grand Complications Perpetual Calendar Chronograph
Of course, our list wouldn't be complete without the Grand Complications Perpetual Calendar Chronograph. At 41mm, this watch is larger than most – perfect for dressing up.
Both the watch and its case are very intricate, but you can easily read the perpetual calendar across the top. Meanwhile, the day, month, date and moon phase are displayed together at 6 o'clock.
At the bottom of the dial, there's an indicator showing whether it's AM or PM, and another one for leap years. To adjust the perpetual calendar, there's a button located between the lugs at 6 o'clock.
Audemars Piguet Royal Oak Quantieme Perpetual
Audemars Piguet introduced its first perpetual calendar wristwatch in 1950. Even now, their wristwatches, like the Royal Oak Quantieme Perpetual, are loved for their top-notch craftsmanship.
This one is beautifully designed, with a month dial at 12 o'clock and a date dial at 3 o'clock. You'll also see the moon phase dial at 6 o'clock and day dial at 9 o'clock. It's a classic layout that you can't go wrong with.
We also love Audemars Piguet's Black Ceramic Perpetual Calendar watch.
Vacheron Constantin Patrimony
The Vacheron Constantin Patrimony is a perfectly sleek men's perpetual calendar watch. It's not too flashy but instead keeps things simple with a minimalistic rose gold frame.
The case is just a little over 8 mm thick, but it manages to accommodate the calibre 1731 and a calendar complication. Unlike other picks on our list, the perpetual calendar is a lot more subtle on the Vacheron Constantin Patrimony.
How to Set a Perpetual Calendar Watch
Once you've scored your first perpetual calendar watch, it's time to set it with three simple steps.
Most modern versions follow this method, but a vintage perpetual calendar watch may need to be adjusted differently. Make sure to consult the manufacturer if that's the case.
Step 1
- Unscrew the crown by turning it to the left until it stops at position 0.
- Turn the crown to the right until the power reserve indicator reaches the highest point, showing a full 60 hours of power.
- If you wear your perpetual calendar watch regularly, it will wind itself as you move throughout the day.
Step 2
- Pull the crown out to position 2 and set the time to 7:50 AM.
- Look for the dot at 1 o'clock to make sure it's 7:50 AM.
- Push the crown back to position 1 and adjust the year, month, and date as needed.
Step 3
- Pull the crown out to position 2 again to set the time.
- Screw the crown back in gently by turning it to the right.
- Be careful not to use too much force, especially if your watch case is made of sterling silver 925.
Takeaway
Over 250 years have passed since Thomas Mudge first created the perpetual calendar complication.
Even in today's age of smartwatches, the classic allure of perpetual calendar watches is still undeniable. Imagine a wristwatch capable of tracking time and date practically forever, without relying on electricity, the internet, or batteries. It's a testament to the unbelievable skills of fine watchmaking.
