How Does an Automatic Watch Work?

Automatic watch article header
By Maverick, 25th of August 2022

The automatic watch has been around for many centuries, but how does an automatic watch work exactly?

These watches are not only beloved by timepiece enthusiasts the world over but automatic watches represent hundreds of years of watchmaking.

Who exactly invented the first ever automatic watch may be a little unclear with some believing Abraham Louis Perrelet to be the father of the automatic watch. Others give credit to Hubert Sarton.

However, one name that is always synonymous with automatic watches is John Harwood. The British watchmaker and watch repair specialist would develop the modern-day automatic watch that we are more familiar with today. Harwood even patented the automatic wristwatch in 1923.

Harwood’s automatic wristwatch took off after World War 1 in favor of pocket watches due to their slimline design and reliable time telling.


A Union Glashütte Automatic movement

What is an Automatic Watch?

Now while that is a fun little history lesson, it still doesn’t answer the question of how does an automatic watch work.

Simply put, an automatic watch is a type of watch made up of many tiny gears and springs that power the watch so it can tell the time as accurately as possible.

Unlike other watch designs, the automatic watch is self-winding. This means it doesn’t run on a battery or it doesn’t have to be wound by hand every day.

An automatic watch’s most defining characteristic is the fact the watch stores kinetic energy when worn and this is then released to power the watch’s intricate mechanism.

Another stand-out feature of the automatic watch is the movement of the second hand. Automatic watch second hand smoothly sweep by the seconds.

How does an Automatic Watch work?

All these little gears and springs and coils sound amazing. But how they all work together is even more mind-blowing.

Wearing the watch has a knock effect of causing a weighted rotor to turn. The energy is all stored in the mainspring.

This begins to power the watch through the gears. The gear train transfers the energy to the escapement. This escapement distributes energy to the balance wheel in perfectly timed intervals.

This in turn pushes the balance wheel back and forth. Every swing of the balance wheel pushes the gear train which then, in turn, moves the watch’s hands.

Key Components of an Automatic Watch

Phew! That all got a bit technical just now and I hope that answers the question how does an automatic watch work.

Let’s break things down even further and get into the parts that make an automatic watch tick…


The rotor is a semi-circular, 360-degree moving weight that kicks off the watch’s movements. Some refer to the rotor as the oscillating weight. No matter what you call it, the rotor moves freely when worn. This winds the mainspring which supplies the watch with mechanical energy. 


This is a coiled metal strip. The mainspring is key to the automatic watch as it stores and slowly releases the energy.

Gear Train

The energy that is released by the mainspring gets the series of gears, known as the gear train, moving. The gear train runs the energy from the mainspring to the escape wheel. 


The crown will be one of the more recognizable pieces on this list. The crown is a little button or wheel outside of the case. When this button is pushed in the automatic watch can be manually wound. When the crown is pulled out the hands on the watch face can be adjusted. 


The escapement is like a watch’s internal braking system. By being designed in two equal parts, the escapement makes sure the energy from the mainspring is released equally.

Balance Wheel

The balance wheel or more affectionately known as the heart of the movement beats in a circular motion to power the watch. It can beat anywhere between 5 and 10 times a second. 

How to Tell if an Automatic Watch is Quality made?

1. Check the Crystal

All watches have a clear casing to show the watch’s face. I mean it would be pretty hard to tell the time otherwise. But not all of these casings are made from the same material.

Most modern watches use either watch faces made from mineral crystal or sapphire. A watch with a sapphire casing usually means the watch is of high quality. Sapphire is extremely durable and almost scratch-proof. 

Unlike mineral crystals, which if scratched will leave permanent damage.  Sapphire casings are the gold standard when it comes to watchmaking and is used almost exclusively by trusted brands.

2. Check the Movement

When it comes to automatic watches, many are made with a clear back. This not only looks amazing as you get to see the inner workings of your watch but it is perfect for inspection when buying the watch.

The likes of Germany, Japan, and Switzerland are all revered for their high-quality automatic watch movements. However, as with any product, there are good and bad suppliers in all countries. It is essential to research the watch supplier and get an idea of their quality. 

3. Does the watch have a COSC Certificate?

COSC stands for Contrôle Officiel Suisse des Chronomètres. This is the body that certifies the accuracy of watches. These more often come with luxury Swiss watches.

If a watch has a COSC cert you can rest assured your watch has passed many tests and tells time extremely accurately. High-quality watches are designed to have an accuracy of +6 / -4 seconds per day.

Pros and Cons of Automatic Watches

Automatics watches are truly a work of art both in their mechanical movement and amazing design. There are many upsides to being the proud owner of a beautiful automatic watch.

However, there are some downsides too. Let us have a look at some pros and cons of these mechanical masterpieces when compared to other wrist watches.

✅ Pro — Aesthetics: This is possibly the biggest pro when it comes to automatic watches depending on whom you ask. All those gears and springs look amazing, especially on an open back casing. It is hard to argue against this one!

Pro — No battery needed/no hand winding: The self-winding mechanism of automatic watches makes them somewhat low maintenance. While all watches need general care and servicing, as long as the automatic watch is worn regularly it should continue working with few problems. 

⛔️ Con — Not the most accurate: The automatic wristwatch is no slouch in the time-telling department. However, as far as watch movement goes automatic watches aren’t the most accurate on the market. The quartz watch is considered a little more accurate compared to automatic watches. 

⛔️ Con — A little Pricey: Due to the amount of time and labor it takes to create automatic watches,  they tend to lean on the pricier side of the watch market.  

The Verdict on Automatic Watches

The automatic watch is a watch design that is beloved by the watch community as a whole, and for good reason. The craftsmanship alone is reason enough to own an automatic watch. The self-winding feature literally asks the owner to place it on their wrist as much as possible.

While there are ups and downs when it comes to this classic watch design, the automatic watch is undeniably an amazing feat of engineering and truly mesmerizing.

Latest Posts You'll Definitely Enjoy...

0 replies

Leave a Reply

Want to join the discussion?
Feel free to contribute!

Leave a Reply

Your email address will not be published. Required fields are marked *