how to use a tachymeter

How to Use A Tachymeter

In this article, we will explore the fascinating world of tachymeters, learn how to use them effectively, and discover their numerous benefits.

The tachymeter is a feature found on the bezel of many chronograph watches, designed to measure speed based on time and distance. While it may seem like a relic of a bygone era, the tachymeter remains relevant even in the digital age. It offers a practical and efficient way to measure speed and distance, without the need for complex calculations or reliance on electronic devices.

Whether you're a professional racer, an avid sports enthusiast, or simply want to make the most out of your watch, understanding and using a tachymeter can provide you with valuable insights and practical applications. So let's dive in and unlock the potential of this versatile tool.

What is a tachymeter and its purpose?

A tachymeter is a scale inscribed on the bezel of a watch that allows the wearer to calculate speed or distance based on the time it takes to travel a predetermined distance. It is most commonly found on chronograph watches, which feature a stopwatch function in addition to the standard timekeeping functions.

The primary purpose of a tachymeter is to measure speed in units per hour, such as kilometers or miles per hour. To do this, the wearer starts the chronograph when passing a known distance marker, and then stops it once the predetermined distance has been covered. The tachymeter scale then shows the speed at which the distance was traveled, based on the elapsed time.

While the tachymeter's primary function is to measure speed, it can also be used to measure distance if the speed is known. This can be particularly useful in situations where GPS or other electronic means of measuring distance are not available or practical.

The history of tachymeters

The concept of the tachymeter watch dates back to the 18th century when French mathematician Pierre-Simon Laplace developed a method for measuring distance and speed based on the time it took to travel a known distance. This method was later refined and adapted for use on pocket watches, and eventually wristwatches, by various watchmakers throughout the 19th and 20th centuries.

One of the earliest examples of a wristwatch featuring a tachymeter was the Rolex Oyster Chronograph from the 1930s. However, it was the Omega Speedmaster, introduced in 1957, that truly popularized the tachymeter as an essential tool for professional racers, pilots, and astronauts. In fact, the Omega Speedmaster was the first watch worn on the moon during the Apollo 11 mission in 1969, highlighting the importance and reliability of the tachymeter in professional settings.

Today, tachymeters can be found on a wide variety of watches, from high-end luxury timepieces to affordable sports watches, making this versatile tool accessible to enthusiasts and professionals alike.

Understanding the tachymeter scale

Before learning how to use a tachymeter, it is essential to understand the tachymeter scale and how it relates to time and distance measurements. The tachymeter scale is typically inscribed on the bezel of a watch, although it can also be found on the dial or even the case back in some instances.

The scale consists of a series of numbers, usually starting with 60 at the 12 o'clock position and decreasing in value as you move clockwise around the bezel. These numbers represent units per hour, such as kilometers or miles per hour, and correspond to the time it takes to travel a predetermined distance.

For example, if the tachymeter scale shows the number 120, this means that if it takes 30 seconds to travel the predetermined distance, the speed is 120 units per hour. The tachymeter scale is typically calibrated to work with a base distance of one kilometer or one mile, but it can be adapted to other distances if necessary.

It's also important to note that the tachymeter scale is logarithmic, meaning the spacing between the numbers decreases as the values increase. This allows for a wider range of speed measurements but can make reading the scale more challenging, particularly at higher speeds.

How to use a tachymeter: step-by-step guide

Now that we have a basic understanding of the tachymeter scale, let's explore how to use it effectively. Here is a step-by-step guide to using a tachymeter to measure speed:

  1. Determine the base distance that corresponds to your tachymeter scale, as well as the unit of measurement (e.g., kilometers or miles per hour). This information can often be found in the watch's user manual or on the manufacturer's website.
  2. Position yourself at the starting point of the predetermined distance and prepare to start the chronograph function of your watch.
  3. When you begin to move, start the chronograph by pressing the designated pusher on your watch.
  4. Continue to travel the predetermined distance, maintaining a consistent speed as best you can.
  5. As you reach the end of the predetermined distance, stop the chronograph by pressing the designated pusher on your watch.
  6. Read the elapsed time displayed on the chronograph and find the corresponding number on the tachymeter scale. This number represents your speed in units per hour.
  7. Reset the chronograph and tachymeter scale, if necessary, to prepare for the next measurement.

To measure distance using a tachymeter, follow these steps:

  1. Determine the speed at which you will be traveling, as well as the unit of measurement (e.g., kilometers or miles per hour).
  2. Start the chronograph when you begin to move.
  3. As you travel, keep an eye on the tachymeter scale and stop the chronograph when the scale displays a number corresponding to your predetermined speed.
  4. Read the elapsed time displayed on the chronograph and use the base distance and time to calculate the distance traveled.
  5. Reset the chronograph and tachymeter scale, if necessary, to prepare for the next measurement.

Practical applications of a tachymeter

While it may seem like a specialized tool, the tachymeter has a wide range of practical applications that extend beyond professional racing and aviation. Here are some examples of how a tachymeter can be useful in everyday situations:

  • Monitoring your speed while jogging, cycling, or driving, to ensure you stay within safe limits or achieve personal goals.
  • Measuring the distance of a hiking trail or running route when GPS or other electronic means are not available or reliable.
  • Estimating the speed of a moving vehicle, such as a train or boat, to determine arrival times or make travel plans.
  • Calculating the average speed of a journey to assess fuel efficiency, optimize travel times, or evaluate transportation options.

The versatility of the tachymeter makes it a valuable tool for anyone interested in measuring speed and distance quickly and efficiently, without the need for external devices or complex calculations.

Benefits of using a tachymeter

There are several benefits to using tachymeter watches, ranging from practical applications to personal satisfaction. Some of these benefits include:

  1. Improved productivity: By measuring speed and distance accurately, a tachymeter can help you optimize your time and resources, ensuring you make the most of every minute.
  2. Enhanced decision-making: A tachymeter allows you to quickly and easily assess various transportation options, helping you make informed decisions that save time and money.
  3. Increased safety: Monitoring your speed while engaging in activities such as driving or cycling can help you stay within safe limits and avoid potential accidents.
  4. Greater self-awareness: Regularly using a tachymeter to measure your speed and distance can provide valuable insights into your personal performance, helping you identify areas for improvement and set achievable goals.
  5. Satisfaction and enjoyment: There's something uniquely satisfying about mastering a skill like using a tachymeter, and it can add an extra element of enjoyment to your watch-wearing experience.

Common mistakes when using a tachymeter and how to avoid them

As with any tool, there are some common mistakes that people make when using a tachymeter. By being aware of these pitfalls and taking steps to avoid them, you can ensure you get the most out of your tachymeter experience:

  1. Misreading the tachymeter scale: Due to the logarithmic nature of the scale, it can be challenging to read the numbers accurately, particularly at higher speeds. Take your time to read the scale carefully and consider using a magnifying glass if necessary to ensure accurate measurements.
  2. Inaccurate timing: Starting and stopping the chronograph at the exact moment you pass the distance markers is crucial for accurate tachymeter measurements. Practice your timing and consider using visual or auditory cues to help you synchronize your actions with the distance markers.
  3. Incorrect base distance: Using the wrong base distance can lead to significant errors in your speed or distance calculations. Double-check the base distance associated with your tachymeter scale and ensure you are using the correct unit of measurement.
  4. Inconsistent speed: Maintaining a consistent speed throughout the measurement process is essential for accurate tachymeter readings. Focus on maintaining a steady pace and consider using a metronome or other pacing device to help you stay on track.


The tachymeter is a powerful and versatile tool that, when used correctly, can unlock a wealth of information and insights about your speed and distance performance. By understanding the basics of how to use a tachymeter, you can harness its potential to enhance your productivity, decision-making, and personal satisfaction.

Whether you're a professional racer, an outdoor enthusiast, or simply someone who appreciates the finer details of a well-crafted watch, mastering the art of the tachymeter can open up a world of possibilities and transform your watch-wearing experience. So go ahead, strap on your favorite chronograph, and start unlocking the potential of your tachymeter watch today!