How to Use a Tachymeter Watch and What is It?

How to use tachymeter on a watch? And what is it exactly? A tachymeter is one of the watch complications that performs a speed and distance measurement. Interesting, right? Among many other functions of watch complications, the watchmaking industry also offers a simple yet practical feature as in the tachymeter. A watch with a tachymeter is often included in certain types of watches, especially racing watches.

But what is the purpose of a tachymeter? Back then, a tachymeter was first introduced as an additional function featured on a chronograph watch. The first chronograph watch was invented by a French watchmaker in 1821 named Nicolas Mathieu Rieussec. However, the manufacturing process took some time until 1913.

Not too far from that period, a tachymeter was added and continued to show its popularity in the aviation or automobile racing industry by the 1930s. A tachymeter might be just an additional function but at the right person, it could be a breakthrough invention.

In this article, we’re going to explore and scrutinize what is a tachymeter and how to use a watch tachymeter. In the end, you might have answered your question that I believe is lingering on your mind, “do people use tachymeter?”. Let’s find out!

What is A Tachymeter on A Watch?

Among many watch features, the tachymeter is barely noticed as it seems to blend in with the bezel. So, what is a tachymeter and what is the purpose of a tachymeter?

A tachymeter is a watch feature that allows the wearer to measure speed using elapsed time over a known distance. It’s not as complicated as it seems although you might be wondering how to use a watch tachymeter and define a certain speed using the scale inscribed around the bezel or the outer dial of the watch.

In fact, a tachymeter is rather a simple feature that determines the speed of movement based on time. You just need to know how to read the bezel with a simple formula that we’ll cover in the later part. A watch with a tachymeter would always feature a chronograph as you need the stopwatch function for the time measurement.

However, a chronograph doesn’t always come with a tachymeter scale. The tachymeter bezel is actually an additional feature for a chronograph watch that would elevate its performance. To put it simply, a chronograph is a stopwatch while a tachymeter is a speed measurement device.

Indicating a tachymeter can also be seen through the bezel. The most common design for a bezel is that it could be rotated to perform a specific task. As an example, a pilot watch that features dual-time complications mostly comes with a rotating bezel, allowing the wearer to adjust the second time by simply operating the bezel. However, the case is different in the tachymeter bezel as it is fixed – not a rotating bezel.

How to Use A Tachymeter on A Watch?

The next question that appears on your mind might be how to read a tachymeter. Besides, do people use tachymeter? The answer is yes for you who are a fan of racing or sports activities. Otherwise, it depends on your preference.

Having a tachymeter would be a useful watch function for those who are closely related to speed measurements — in common cases athletes as it primarily functions to determine speed. Reading a tachymeter only needs a simple formula that works based on some basic math.

In an hour, there are 3600 seconds and you need this information to work on the formula. It defines that a tachymeter dial is equal to 3600 divided by the elapsed time in seconds. As a result, the printed tachymeter scale is valid for all time up to one minute from approximately seven seconds.

In determining speed using a tachymeter, you first need to know the distance between the two points you’re going to measure, let’s say points A to B. Once, you know the distance, you can press the chronograph pusher to start the stopwatch when the vehicles at the racing car or person at the running competition start moving.

Then, stop the chronograph when the object reaches point B. This is where you need to read the bezel to know the speed. Find where the second hand is on the minute track and that would tell the speed of the object. The indicated number on the chronograph tells about the seconds passed while the tachymeter scale corresponds to the speed traveled.

Let’s get this in an illustration to make it clearer. You are watching a car racing event and you want to measure the speed of the car. Based on the information you got, the distance between curve A and curve B is exactly 1 kilometer. Using the chronograph, you notice that it needs 20 seconds to cover this distance while the tachymeter scale reads 180. This means that the average speed of the car was 180 km/hour.

Taking on another example, what if the identified distance is only 200 meters as in the case of a running competition. For example, the runner needs 20 seconds to complete that race and the tachymeter scale indicates 180. However, you need to be careful as the distance is only 1/5 of a kilometer. So, the calculation should be 1/5 of 180 which equals 36 km/hour as the actual average speed of the runner.

Knowing how to use a tachymeter on a watch to calculate speed would help you to determine how fast you are when traveling from one place to another. In addition to that, it functions independently on a specific distance unit (be it kilometers or miles) as long as you use the same unit in all your calculations. By that means, an 80 reading on the tachymeter scale can be the same as both 80 kilometers per hour and 80 miles per hour.

5 Reliable Tachymeter Watches for Measuring Speed

Now that you’ve understood what is a tachymeter and how to use a watch tachymeter, I believe that having some recommendations would please you to know more about this feature. So, let’s get straight to 5 reliable tachymeter watches.

Seiko Prospex Speedtimer Chronograph Blue Ref. SBDL087

When it comes to design, Seiko is unbelievably never disappointing, including the one presented in Prospex Speedtimer Chronograph Blue. A tri-compax layout and the color combination bring a pleasing view to the eyes. Along with the chronograph, Seiko also provides a tachymeter scale engraved on the bezel. Seiko Prospex Speedtimer Chronograph Blue Ref. SBDL087

The overall surface of the watch has been well-polished including the fixed black polished bezel. If you take a closer look at the finer details, you might notice how the bezel slopes downward to divide the markers and etched tachymeter numerals on the outer perimeter.

Hamilton Jazzmaster Face 2 Face II Auto Chrono

The next tachymeter watch might look a little complex in terms of design. Instead of having a common design, the Hamilton Jazzmaster Face 2 Face II Auto Chrono brings the watch as if two watches in one with its distinct rotating case. However, if you take a closer look, you’ll notice each feature it offers including the tachymeter scale.

At the center of the watch, you can see the central chrono that allows three different readings through the measurement scales printed on the crystal and dial. Together with the tachymeter, this Hamilton watch also has a telemeter and a pulsometer.

Steinhart Marine Officer Bronze

A splash of bronze for a chronograph truly hits differently as it elevates the vintage charm of the watch. The Steinhart Marine Officer Bronze brings the idea of tachymeter from the land to water sports. Well, you might as well need a speed measurement tool for yachting.

The tachymeter scale is engraved on the bezel brushed finely in a full bronze – this somehow provides sufficient space for the scale.

Le Jour Le Mans Chronograph Gunmetal Grey Ref. LJ-LM-015

Le Jour’s racing chronograph has become an important milestone for the brand to revive after the Quartz crisis. The Le Mans Chronograph Gunmetal Grey is one of the gems. Featuring a tri-compax layout, the tachymeter scale is inscribed on the bezel – which makes the bezel fixed. Yet, as a racing watch, the tachymeter and chronograph are already a great combo. Le Jour Le Mans Chronograph Gunmetal Grey Ref. LJ-LM-015

Aristo Flieger 40 Chronograph 3H129 – Sapphire

A dandy timepiece to accompany your day-to-day activities, the Aristo Flieger 40 Chronograph 3H129 appears in a chic appearance. A tachymeter scale can be spotted on the edge of the dial along with its chronograph complication.

This Aristo watch is equipped with pushers for the chronograph, that way it will be more convenient to operate the crown for its own function.

Do You Need A Tachymeter Watch?

Now that you’ve understood what is a tachymeter, it’s time to think and consider whether or not you need a tachymeter in your watch. A tachymeter might not be everyone’s thing as for some, the function isn’t that crucial for their daily activities.

But if you are an athlete or even a fan of sports activities who is a friend of speed, a watch with a function to determine the average speed could be useful.

Besides, for me, the tachymeter scale wouldn’t give much bother – although some people consider it cluttered the watch face. Looking only at the scale might cause you confusion and think of how complicated a tachymeter is. Meanwhile, all it takes is just a routine and once you are familiar with it, you could even tell the speed with a simple glance.

Know the distance and you’re ready to work with a tachymeter. Fortunately, you’ll also be spoilt for choice as this function is mostly available along with impressive watches. As such, do you need one?

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