Accuracy is very important in a wristwatch. After all, it is the main reason why people wear one.
As you probably know, no wristwatch without atomic timekeeping is 100% accurate. In addition, with mechanical movements, it is even more difficult to achieve perfect accuracy due to the fact that they consist of hundreds of parts, and beat thousands of beats per hour.
But many watch brands have invested heavily in research, development, and testing in order to improve the accuracy of their watches. One brand that has put great emphasis and importance on this is Rolex. As a result, Rolex has made huge progress when it comes to the accuracy of its timepieces, and today, Rolex’s watches are known for being some of the most accurate automatic watches in the world. And they are known for their excellent accuracy for years to come. So much so that Rolex now recommends service intervals of about 10 years.
Naturally, Rolex has made some huge innovations and improvements over the decades that have led its watches to achieve greater accuracy, greater reliability, and improved durabilitet. And it’s important to highlight the fact that this isn’t just some marketing gimmick that do not mean anything. In fact, Rolex’s improvements have led to greater improvements to its accuracy in practice.
It’s self-explanatory why you want to have a watch with good accuracy. A watch with poor accuracy, whether it is quartz or mechanical, will eventually deviate so much that you will get a wrong indication of what the time is when reading it. The negative part about this is that it may eventually come to the point where you cannot trust your watch, and instead opt for looking at the time on your phone, which removes some of the point of even wearing a wristwatch for many.
The good news is that Rolex watches are some of the most accurate mechanical wristwatches on the market today. And this is just one of many reasons why Rolex watches are so greatly appreciated.
Rolex watches accuracy today
All Rolex watches manufactured today have to go through the exact same tests and have the same requirements when it comes to accuracy. Therefore, all Rolex watches that leave the factory are, in Rolex language, called ”Superlative Chronometers”.
What does this mean?
Rolex says this about the Superlative Chronometer designation:
”This exclusive designation attests that it has successfully undergone a series of specific final controls by Rolex in its own laboratories according to its own criteria, in addition to the official COSC certification of its movement. This unique testing of the chronometric precision of the cased-up movement, as well as of the watch’s waterproofness, self-winding and power reserve, pushes back the boundaries of performance and makes Rolex the benchmark for excellence in mechanical watches.”
Today, all Rolex watches have a specified accuracy to +/- 2 seconds per day. This is an extremely impressive accuracy that only a handful of watch brands are able to achieve with for their mechanical watches. In fact, it is not uncommon to see mechanical watches with an accuracy of 5 seconds or even 10 seconds of accuracy per day. Therefore, it’s safe to say that Rolex has made some very impressive achievements and accomplishments when it comes to the accuracy of its watches.
The great thing is that Rolex watches come with a warranty period of five years. And the accuracy is something that is covered under the warranty. If you start to notice that your watch isn’t keeping perfect time according to the specifications, you can simply take it to a Rolex official retailer and they will help with bringing it back to the specified accuracy.
Rolex introduced its Superlative Chronometer Certification in March 2015 with the launch of the new Day-Date 40. Prior to this, Rolex did have stringent tests on its movements, but this designation took it one step further. Following this, Rolex extended its Superlative Chronometer Certification to its entire lineup of watches, meaning that all modern Rolex watches are now specified to -2/+2 seconds accuracy.
However, this hasn’t always been the case, and this is why, prior to 2015, Rolex watches did not have this specified accuracy. So let’s look at what Superlative Chronometer means, and what Rolex did before this.
Rolex COSC and Superlative Chronometers
Before 2015, Rolex sent all of its movement to be tested by the independent COSC chronometer certification testing institute. After 2015, this did not change, but Rolex did introduce an additional step to further improve the accuracy of its movements.
During the COSC testing, Rolex watches are tested for a total of fifteen days, in five different positions, at three different temperatures. The accuracy allowed by COSC is -4/+6 seconds per day. With that said, Rolex watches prior to 2015 met an accuracy of -4/+6 seconds per day. But after 2015, Rolex added an additional step in its testing process in order to guarantee the accuracy of +/- 2 seconds per day.
This step involves submitting the watches for internal certification after the COSC testing. In fact, Rolex’s in-house testing is even more stringent and strict than COSC, but the brand felt that they did not want to abandon the COSC certification, likely to take advantage of the reputation within Swiss watchmaking this has, but also to make sure that the movements are externally tested first in order to achieve more credibility.
What stands out about Rolex’s own in-house testing is that involves simulating the conditions in which a watch is actually worn.
Different factors affect the accuracy of mechanical movements
The accuracy of mechanical movements is affected by a number of different factors. One of the key factors is gravity. A watch may be highly accurate in one position, but not as accurate in another.
This is why Rolex puts a lot of effort into testing and adjusting its watches to different positions. The balance wheel can adjust to compensate for losses and gains in different positions, and this is one of many reasons why Rolex watches tend to keep their accuracy within the specifications, even in different positions.
Common Rolex watches and their accuracy
Rolex Submariner 124060 accuracy: +/- 2 seconds per day
Rolex Submariner 126610 accuracy: +/- 2 seconds per day
Rolex Daytona 116500LN accuracy: +/- 2 seconds per day
Rolex Explorer 226570 accuracy: +/- 2 seconds per day
Rolex Explorer 214270 accuracy: +/- 2 seconds per day
Rolex Datejust 41 accuracy: +/- 2 seconds per day
Rolex Datejust 36 126234 accuracy: +/- 2 seconds per day
..and the rest of the watches in the modern Rolex collection share the same specifications in terms of accuracy due to the fact that they are now all Superlative Chronometers. The really are very few brands that can compete with this accuracy when it comes to mechanical movements today, and Rolex is certainly at the forefront of this. If you want even greater accuracy, there are some quartz and atomic clocks that can beat it, but there’s just nothing like a good mechanical watch.