Watch Complications Explained

“It’s complicated.” The phrase suggests something that is hard to understand or explain. A “complicated” watch, however, is usually viewed as desirable and a source of purpose and pleasure by enthusiasts.

The primary function of a watch is to tell the current time in hours, minutes, and, usually, seconds. A “complication” is a watch function that provides additional information beyond those three measurements.

Complications are usually visual, conveying additional details through extra dial print, subdials, apertures, bezels that calculate elapsed time and speed of moving objects, or additional hands that indicate how much power is left in the watch’s mechanism, or even the current time on the other side of the world.

But complications can be pleasing to the ears as well. Acoustic complications include alarms that countdown or sound at a set time, “repeaters” that ping or chime every minute, quarter hour, and hour, enabling the wearer to tell the time by sound alone, and even “music boxes” that play tunes.

In this article, I describe a few of the most popular complications available today. After reading this, you may discover that a “complicated watch” can be a good thing and a nice pickup for your collection.

Date Complications

A simple date complication indicating the numerical calendar day is the most desired and useful for an everyday wear watch.

A self-changing date complication, first introduced in the 1945 Rolex Datejust, is usually accomplished with a date wheel inside the watch case that rotates to the next day automatically as the time passes 00:00 hours (midnight). 

There is an aperture or date window, most often located at the 3 o’clock position, but sometimes at 4:30 or 6:00 as well. The day of the week is sometimes added, either as an abbreviation alongside the date at 3:00 or at 12:00 using the full name.

In addition to apertures, some watches use an extra hand called a “pointer” to show the date. These usually have the Arabic numerals 1-31 located along the outer edge of the dial in an area called the “chapter ring” or in a smaller dial within the main dial (“subdial”).

Pointers are often used in perpetual calendar watches with very complex—and expensive—mechanisms that can advance the day, date, month, and year correctly, including leap years, until the year 2100 without resetting as long as the watch is kept running. An annual calendar watch tracks the same information but must be reset every year.

Chronograph Complications

Another popular complication is the chronograph. “Chronograph” is derived from the Greek language and means “time recording”. Chronographs track both the current time and the elapsed time of an event. Most modern chronographs have a start/stop pusher at 2 o’clock position and a reset pusher at 4 o’clock. 

A long timing seconds hand is usually used that extends to seconds indices at the dial’s edge. In addition, subdials can track current running seconds as well as elapsed timing hours, minutes, and even fractions of seconds.

There are several variations of chronographs that go beyond the basic “stopwatch” format. 

A tachymeter is a numerical scale on the bezel that allows the calculation of the speed of a moving object over a set distance in either mph or kph. A telemeter scale on the bezel or dial can estimate the distance from an event that is seen and heard (e.g. a lightning strike and ensuing thunder), while a pulsometer scale can compute heart rate in beats per minute. Sometimes, all three are combined in one chronograph.

In addition, there are chronographs with more complicated mechanisms that fine-tune the measurement of elapsed time. A “rattrapante” (French for “catch up”) is a “splits seconds” chronograph that uses two timing seconds hands to measure total elapsed time as well as “split” or lap times. A “flyback” chronograph allows the user to start and stop the timing seconds hand and reset to zero with a single press of a pusher.

GMT/World Time Complications

GMT and World Time complications enable the wearer to track the time in different timezones around the world. “GMT” stands for Greenwich Mean Time, the system that designates 24 global timezones with a reference “Zero Hour” linked with the longitudinal Prime Meridian, which runs through the Royal Observatory near London.

GMT watches are typically four-hand watches with a GMT hand that tracks a 24-hour scale on the bezel, which may be rotating or stationary. There are two basic types: traveler (aka “flyer”) and desk (aka “caller”). 

A traveler GMT has a jumping local hours hand, which can be set independently when arriving in a different timezone without interrupting the watch’s timekeeping. The GMT hand stays on the time back home.

In contrast, a desk GMT has a jumping GMT hand that can be set independently to a different timezone while the local time keeps running, making it ideal for someone staying put but needing to know the time at a different location. A rotating bezel can track a third timezone with both traveler and desk types.

A world time complication can show not just 2-3 timezones but any time across the world. A common characteristic of all world timers is a list of reference cities representing the 24 global timezones and a 24-hour scale. The city list is usually located on an outer chapter ring, which may be stationary or rotating or on a rotating bezel. 

The 24-hour scale is usually located on an inner chapter ring, which can be set and rotated through every city over the course of the day. Other world timers use pushers that move some combination of the reference cities, 24-hour scale, or local hours hand.

It all sounds a little confusing and, well, “complicated”, but in real life, everything works out fine once you figure out your model’s mechanism.

Moonphase Complications

Some form of “moonphase” clock has been in use since ancient times when tracking the lunar cycle yielded important information regarding planting, harvesting, hunting, and fishing.

These days, a moonphase watch complication uses a rotating disc depicting the sunlit moon’s phases over a 29.5-day period, which is seen through a decorative, cutout aperture on the front of the dial, sometimes round, but usually arc-like, similar to a half-moon. 

A moonphase complication is not particularly accurate—or useful—but it is stylish and adds nice touches of color and additional interest and motion to the watch face that make them popular among collectors.

Though often associated with expensive, high horology, moonphase complications are also available in more affordable entry-level mechanical watches and every price point in between.

Tourbillons

When it comes to timekeeping, gravity is not a friend. The small components of a mechanical watch are affected by gravitational forces, resulting in “positional errors”, which adversely affect accuracy.

A tourbillon (French for “whirlwind” which describes the mechanism’s swirling motion) is a complication that mitigates these errors, making it, in effect, an “anti-gravity” machine. 

Basically, the balance wheel, balance spring, and escapement, the intricate parts most susceptible to positional errors, are located inside a rotating cage that helps average out gravitational forces in a mostly stationary timepiece such as a pocket watch.

The tourbillon was created by renowned French watchmaker Abraham-Lewis Breguet in 1795 and patented in 1801. Since that time, the tourbillon has evolved from the single-axis model of Breguet to more complex ones that use multi-axes, combinations of tourbillons, “flying” tourbillons mounted so they appear freestanding, and even ultra-sophisticated “gyro” ones that drive perpetual calendar watches.

There is controversy as to whether or not tourbillons improve accuracy significantly in modern watches that are non-stationary and rotating with the motion of the wearer’s wrist. 

But no one denies the intricate beauty of these complications seen through open, skeletonized dials and display casebacks. They can mesmerize and hypnotize for hours and have your boss frowning in chagrin at the inverse relationship between your watch addiction and office productivity.

Since tourbillons are complex and difficult to manufacture, they tend to be very expensive and associated with high-end horology. However, improvements in manufacturing and technology enable some companies to offer tourbillon watches for lower prices.

Power Reserve Indicators

A power reserve indicator is a watch complication that shows how much potential energy remains in a mechanical watch’s mainspring. Think of it as your watch’s “fuel gauge”. 

If you don’t wear a mechanical or automatic watch every day, it’s useful to know how much is “left in the tank” before you strap it on again, especially since a more fully wound mainspring is associated with greater accuracy.

Power reserve indicators are most often seen on dials and may take the form of a hand moving along an arc-shaped scale or within a subdial. Other dial indicators include bar or linear indicators that use a +/- scale or fill up as reserves decrease and color-coded gauges that vary as power levels change. Some people prefer a less cluttered dial, so there are watches with power reserve indicators on the movement, which can be seen through a display caseback.

Like tourbillons, some dismiss power reserve indicators in modern watches with large power reserves and self-winding, automatic movements, believing they are a needless feature from the past. However, one person’s superfluous fluff is another person’s desirable design element. Like beauty, a watch complication is “in the eye of the beholder”.

Mechanical Alarms

We set most alarms these days with our cell phones and digital watches and clocks, so mechanical alarm complications are much less common and cherished than in years past. But as one who owns mechanical watches in part to push back against the creeping tide of digitization and form connections with both my watches and the past, I say, “So what?”

A mechanical alarm complication allows the user to set an alarm within a 12-hour period. The first mechanical alarm watch was created by Eterna around 1914.

 But arguably the most iconic was the 1950s era Vulcain Cricket with a separate barrel system for the alarm that emitted a cool chirping sound, hence the name, and was famously associated with U.S. presidents such as Dwight Eisenhower and Richard Nixon, among others.

There are several other modern watch companies that still offer fine references with mechanical alarm complications, including Tudor, Patek Philippe, Breguet, Jaeger-Lecoultre, and Oris, to name a few. Here’s a link to the Exquisite Timepieces website, which features some of these.

I personally own two watches with mechanical alarms, and not only do I find them handy to wake me up from a catnap, but they also encourage me to slow down and engage with my watch, thereby nurturing the wearer-watch “connection”.

The reward consists of soft, soothing, Zen-like “dings”. Sometimes, I set an alarm for no other reason than to breathe deep and calm my soul.

Minute Repeaters

From mechanical alarms, we transition to the most complex acoustic complication—the minute repeater.

A minute repeater allows the user to tell time through a series of different auditory tones produced by hammers striking gongs. They were originally designed for telling time in the dark and for the visually impaired. 

Not surprisingly, Abraham-Louis Breguet, father of the tourbillon, also invented the first ones in the mid-18^th century. Unlike church bell chimes or grandfather clocks, which strike every quarter hour and hour, minute repeaters chime to tell time to the exact minute.

This is accomplished using an independent chiming mechanism that can be switched on or off—so yes, you can “mute” it. The actual tones and sequencing can differ from brand to brand. 

To illustrate, Patek Philippe uses a lower tone for hours, a two-toned sequence for quarter hours, and a higher-pitched single tone for minutes. For example, to designate 7:47, the minute repeater would strike seven low tones, 3 two-toned sequences, and 2 high-pitched single tones.

There are repeater variations with other sequences and pitches for hours, quarters, half-quarters, 10 minutes, 5 minutes, and single minutes, as well as “dumb” repeaters that don’t chime audibly but instead vibrate.

Along with tourbillons, minute repeaters are premium mechanisms that, while certainly not absolutely necessary for modern times, are nonetheless venerable and sought-after complications. 

As such, they are also very expensive. However, some companies offer less complex hours-only repeaters that still give you that calming chime every 60 minutes at a more affordable price point.

Conclusion

While time-only watches can certainly be aesthetically clean and appealing, we only experience the full range of watchmaking artisanship and functionality when we consider the many complications available in modern timepieces. If “variety is the spice of life,” then watch complications are the cinnamon, cumin, and paprika of horology.

Still, be careful and go easy—a little bit of complication can go a long way.