How Do Automatic Watches Work?

An automatic watch, also called a self-winding watch, requires nothing more than just regular wear to keep running. That’s because it gets its energy from the movement of the wearer.

But how does an automatic watch exactly work? How come they last longer than a quartz watch or a battery-powered watch? Don’t worry, we’ve got it all covered here.

Whether you’re a veteran watch color, curious enthusiast, or someone new to watches, we’re here to make you better understand these ticking machines that many people have grown to love. To start on the right foot, let’s first understand…

The Fundamental Parts of an Automatic Watch

The following are the fundamental parts of every automatic watch:

1. Mainspring

The mainspring serves as the power source of an automatic watch movement. It is a metal spiral where the watch power is stored when it’s tightened and wound. Once the mainspring winds, the untightening or the force of retraction turns the wheel thus powering the watch. 

Imagine this part of an automatic watch as the power plant. For instance, Rolex caliber’s 3255 movement has a long mainspring compared to its other movements. It means it takes longer to retract and has a longer power reserve, usually around 70 hours.

2. Crown

The crown is found on the side of the watch and is used to set the time and date. This all-encompassing mechanism of functionality in an automatic watch is used to wind the mainspring, providing power and energy to the internal movement. 

3. Balance Wheel and Hairspring

The balance wheel (sometimes referred to as a balance spring or hairspring) is like the pendulum in a grandfather clock. It is an internal component that rotates back and forth and beats five to 10 times per second. The balance wheel is so important in an automatic watch because it serves as the time-keeping agent or the watch’s regulator.

4. Escapement

The escapement is the mechanical linkage comprising the pallet and the escape wheel with “teeth.” In every swing of the balance wheel, a “tooth” of the escapement wheel is released to advance the watch’s hands and the rest of the escapement wheel is locked by the pallet. 

The sudden stopping of the escapement’s tooth generates the ticking sound you hear when you hold the watch near your ear.

So, on the whole, the escapement works like an internal braking system, stopping the wheels in the timepiece from spinning out of control. 

5. Reverser

The reverser in an automatic watch is the mechanism that transfers the energy from the motion to the mainspring. Regardless of which way the mainspring is turning, the reverser enables the rotor to still wind it properly.

6. Dial Train

Dial train self-winding watches or automatic watches are just another series of gears like the gear train. It works by transferring the equal parts of energy from the watches’ balance wheel into the watch’s hands, causing the hands to move.

7. Jewels

Watch jewels – or jewel bearings – in automatic watches are tiny pieces of synthetic rubbers put in the center of the gear or high-friction areas to prevent the parts from wearing out. For instance, it is placed in the center of the wheel since it is constantly turning for an automatic movement.

8. Rotor/ Oscillating Weight

A rotor or oscillating weight in automatic or manual watches is the half circle-shaped metal weight linked to the movement that swings freely in 360 degrees as the wearer’s wrist moves. When the wearer moves, so does the rotor. Such a metal weight even transfers powers to the mainspring then twists it.

All right, now let’s find out how do automatic watches work.

How an Automatic Watch Works

You are literally what makes the automatic watch works 

You, as the wearer, are literally the reason why an automatic watch works. The reason being an automatic watch is self-running. The “heart” or the inner workings of the automatic watch beats through the movements of your wrist

What winds the gears within the “heart” is the rotor, which is a semi-circular weight mounted on the movement. The rotor moves back and forth to store energy. Essentially, your movement as the wearer is what moves the automatic watch forward. It, therefore, creates a connection between you and your watch.

A closer look at an automatic watch’s manual winding

Does this mean you no longer need to wind an automatic watch? Well, the answer is you still need to. For you to better appreciate why you still need to manually wound an automatic watch, picture the mainspring inside the timepiece.

On your purchase of a new automatic watch, its spring is completely unwound. Once you move the watch around and set the time and date, it will cause the rotor to spin and it will start winding the mainspring. 

Although it gets the timepiece running, it will still not be enough to fully tighten the mainspring. A fully wound mainspring creates a very strong driving torque and equals the best possible timekeeping since you can use the power reserve to its full capacity.

Therefore, it is important to wind the crown first for about 30 to 40 times to completely wind the mainspring. The moment the mainspring has been fully wound and then the timepiece is worn on an active wrist, the oscillating weight will continuously wind the mainspring.

Automatic watch winder – what is it and do you need one?

There are some people who don’t like winding their automatic watch or automatic watches at all. So, their remedy is to put their watch in an automatic watch winder at night. 

An automatic watch winder is an electronic object or a tabletop box that provides people the convenience of not having to manually wind and reset their watches, especially if they have too many in their collection. Since they cannot wear all of their automatic watches at the same time daily, they need to invest in an automatic watch winder to regain functionality.

Manually winding your collection of watches regularly can be tedious. So, our recommendation is you can invest in a watch winder if you can afford it and if you have lots of watches in your collection that need care and maintenance. The good thing about an automatic watch winder is that it gently rotates an automatic watch to keep it running.

Do know that watches use oil to lessen the friction in their moving parts. When it stops, it could alter the distribution of the lubricant in the watch’s moving components. Plus, constant oil pooling lessens the timepiece’s accuracy and affects its service life. To prevent this from happening, use a watch winder.

On the other hand, if you don’t have that many automatic watches in your collection and you keep up with the regular watch service intervals, you won’t really need to invest in a watch winder. Your timepiece will still be all right even if it just sits still on your nightstand.

Pros and Cons of Automatic Watches


  • Inexpensive luxury 
  • Precious investments
  • High power reserve
  • Boost your confidence and style
  • Their self-winding capability set them apart 
  • Higher water-resistance
  • Energy-efficient
  • Long-lasting aesthetics and functionality
  • Prevent excessive wear and tear
  • Smooth movement
  • Save energy and environment – only your arm’s movement winds the mainspring


  • Usually bigger and heavier
  • May require a reset/ loss accuracy over time
  • Require regular tune-up
  • Smartwatch competition

Automatic Movement – Differences Between Mechanical and Quartz

By now, you may already know that a watch movement or “caliber” drives all timekeeping functions. But what are the differences between quartz and mechanical? Are automatic watches quartz or mechanical?

The answer is: an automatic watch is a mechanical watch. 

Mechanical (manual vs. automatic) movements

A manual mechanical watch movement is hand-wound and it requires daily winding to put tension on the mainspring. An automatic mechanical movement, on the other hand, features an additional free-spinning rotor. This rotor spins in response to the natural body movements and it eliminates the need for daily winding, as long as you keep wearing the watch.

Quartz movements

Quartz movements require minimal maintenance, tend to be low-cost, and are very accurate because they have few moving parts and are battery-powered.

How quartz movements work is simple, no winding required. The batteries inside the watch case send electric signals to the quartz crystal that causes it to vibrate 32,768 times per second. Those vibrations are then converted into one electric pulse once a second. That’s why quartz movements are more accurate than mechanical watches. Meanwhile, automatic quartz watches combine the self-winding rotor mechanisms to generate electricity as their timing element.

Mechanical watches are often chosen over quartz watches because of their high level of craftsmanship and quality.

Some of Our Top Automatic Watch Picks

Tudor Black Bay Fifty-Eight – Best Tudor Automatic Watch of All-Time

The Tudor Black Bay Fifty-Eight Automatic Black Dial Men’s Watch is definitely one of the best automatic watches out there as it carries bits and pieces of the brand’s past. And in case you wonder why it’s called 58, that’s because the design is that of Tudor’s 1958 watch revered as the Big Crown watch.

It is one of the most talked-about automatic watches because it’s got the size of the vintage Tudor Submariner with thick bevels, and a case with great visual definition and vintage charm. This watch features a black dial, luminous gold-tone snowflake-shaped hands, a black and gold fabric band, and a silver-tone stainless steel case.

[Related post: Tudor Black Bay Chrono Vs Rolex Daytona]

Seiko Prospex SPB143 – Best Classic Seiko Watch

how do automatic watches work

The next watch on our list that uses automatic winding is the Seiko Prospex SPB143. Marketed above more entry-level fare, this watch offers an upper tier of the Seiko Prospex lineup. It has finer details and finishing and comes with an upgraded movement. 

It features 13.15 mm case thickness and 40.5mm diameter. The size is just right on the wrist. Plus, its strap versatility makes it more special. It is both foolish and comfortable at the same time.

The Seiko Prospex SPB143 is also water-resistant for up to 660ft. Or 200m. Its accuracy is +25 to -15 seconds per day. Beyond its material, it has a thicker bezel and the guardless crown adds presence to the timepiece without adding a problematic proportion.

Hamilton Intra-Matic Auto – Best Vintage-Inspired Automatic Watch

how do automatic watches work

Another automatic watch that stands out for us is the Hamilton Intra-Matic Automatic Watch. For one, it has the so-called panda dial, meaning the sub-dial registered are made in black while the background is white. 

The hands are clean and very simple, the way we especially prefer it. The hour and minute hands are made in polished metal, and have applied Luminova to them. As for its strap, it certainly adds elegance and makes the watch more classy and formal. A plus point for us also is that it has 60 hours power reserve, with a 28800vph frequency, and is water-resistant for up to 330 feet!

Overall, the Hamilton Intra-Matic Auto watch is perfect for people who enjoy vintage designs and chronograph watches but want the durability and reliability of a modern timepiece. 

Tissot Men’s Chemin Des Tourelles Powermatic 80 – Best Value Automatic Watch With Exceptional Power Reserve

how do automatic watches work

The Tissot Men’s Chemin Des Tourelles Powermatic 80 is our top choice for the best value automatic watch with an exceptional power reserve of up to 80 hours. Well, it may not be the longest power reserve as compared to Hublot MP-05 LaFerrari’s 1,200 hours or up to 50 days of power reserve, but it certainly is not as expensive either.

Its movement is Swiss automatic and is a timepiece that combines precision, contemporary and traditional design, and luxury. It definitely stands out!

Automatic Watches FAQ

Is it okay to shake an automatic watch?

Yes, it is okay to shake an automatic watch as long as you don’t do it violently. Vigorous and rapid shaking may cause automatic wristwatches to lose or gain seconds, affecting their accuracy. Moreover, extreme movements can damage the mechanical parts.

Do automatic watches need to be worn all the time?

Not necessarily. Automatic watches that are worn for at least 8 to ten hours every day will keep running as long as the arm movement is efficient. If not, perhaps due to your lifestyle, you may have to manually wind it at least once a week.

How do I know if my automatic watch is fully wound?

In automatic watch movement, you will know when the mainspring is fully wound because you will feel a resistance plus the winding stops working. Most automatic watches reach a maximum power when the crown is wound 30 to 40 times, although this can vary. 

Can an automatic watch last a lifetime?

Yes, of course. With regular maintenance and care, a high-quality automatic watch made by the finest craftsman can surely last a lifetime.

Are automatic watches reliable?

Yes, automatic watches are reliable, although it still depends on various factors. If the battery-free timepiece meets high-quality standards and comes from a reputable brand, it usually is reliable regardless of how much is the price.

On the other hand, less reliable automatic watches would gain or lose up to two seconds a day. This can cause inaccuracy of 6 to 12 minutes in a year. All that considered, it will still serve its purpose as long as you reset it every month or week.

Wrap Up: An Automatic Watch is Worthwhile to Own!

how do automatic watches work

There you go, watchfam.

We hope you find this article helpful as you learn more about automatic watches, especially how they work. And whichever watch you love, based on your preference and budget, is ultimately the best automatic watch for you!

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