Why Your Rolex Might Be Running Fast (or Slow)

Most mechanical watch owners will eventually notice a little inaccuracy compared to their phone or computer clock. Maybe your Rolex is thirty seconds fast. Maybe it’s running a minute slow. Or maybe you check it for the first time in a while and realize it’s drifted a bit more than that. It’s rarely a sign of trouble—mechanical watches are precise machines, but they’re still mechanical. Small shifts are part of how they work.

Those changes can tell you something, though. Depending on how you wear, store, or even where you set your watch down, the movement inside can behave differently day to day. Here’s what might be happening when your Rolex starts running a little fast—or a little slow.

How Accurate a Rolex Should Be

Image Source: SJX Watches

Every Rolex leaves the factory tested to a strict standard. The Contrôle Officiel Suisse des Chronomètres (COSC) certifies Rolex movements at −4/+6 seconds per day before casing. Rolex then goes further, testing each fully assembled watch to its in-house Superlative Chronometer standard of −2/+2 seconds per day.

Those numbers sound exact, but they’re measured under controlled conditions—static, temperature-stable, and perfectly positioned. Real life isn’t so predictable. The way you wear, rest, or even store your watch affects its timing slightly, and a deviation of a few seconds a day is perfectly normal. Consistency matters more than perfection: a steady +2 or −3 seconds per day means the watch is healthy and well-regulated.

Positional Variance: Gravity and Habit

Rolex Explorer II on rubber strap (resting crown-side up)

Mechanical movements are sensitive to gravity. When a watch rests in different positions—dial up, crown up, crown down—the balance wheel and hairspring behave slightly differently. This is known as positional variance, and it’s why some owners notice their watches speeding up or slowing down depending on how they’re left overnight.

The effect can be minor—a second or two either way—but it’s enough for collectors to take note. Some even “regulate by resting position,” intentionally setting the watch crown-up or dial-down to offset a consistent gain or loss. It’s one of those subtle, analog rituals that come with owning a finely tuned mechanical machine.

Magnetism: The Modern Culprit

In today’s world, magnetism is one of the most common causes of sudden, noticeable inaccuracy. It happens when the hairspring—the delicate coil that regulates timing—becomes magnetized and its coils begin to stick together. The result is a faster oscillation rate, sometimes causing a gain of 30 seconds or more per day.

Magnetism is everywhere: laptop speakers, phone cases, magnetic bag clasps, even certain appliance motors. The good news is that it’s easy to diagnose and fix. A demagnetizer or a quick visit to a watchmaker can completely restore accuracy without opening the case.

Rolex Syloxi (Silicon) Hairspring. Image Source: Rolex

Rolex has spent decades engineering around this invisible threat. The Parachrom hairspring, introduced in the early 2000s, uses a niobium-zirconium alloy that’s largely unaffected by magnetic fields and temperature changes. Later came the Syloxi hairspring, made of silicon—a material naturally resistant to magnetism—used in select models like the Oyster Perpetual 34 and Lady-Datejust. In 2015, Rolex’s Chronergy escapement debuted with nickel-phosphorus components that also resist magnetism while improving efficiency.

Most recently, the Dynapulse escapement found in the new Land-Dweller shows where Rolex is heading next: refining both energy transfer and magnetic stability at once. While other brands have adopted full soft-iron shields, Rolex continues to fight magnetism at the material level, making thw watches more resilient without the bulk.

Shock, Vibration, and Everyday Wear

Rolex Daytona 126500LN. Image Source: Monochrome Watches

A mechanical watch is designed to move with you, but sharp or repetitive impacts can affect its accuracy. Sudden shocks can shift internal components by microscopic amounts or temporarily affect balance stability. Rolex’s Paraflex shock absorbers, introduced in 2005, help protect the balance staff—the most delicate part of the movement—but physics still applies.

Repeated vibration, like during a golf swing, can nudge regulation slightly over time. Even tossing your watch loose into a bag can lead to small knocks that build up. A simple way to avoid that: store it securely in an Everest watch roll or pouch. Protecting your watch from unnecessary shock helps preserve both its timekeeping and long-term wear.

Regulation and When to Worry

Image Source: Bob's Watches

If your Rolex consistently runs a few seconds fast or slow, it may just need a minor regulation. That process doesn’t involve opening or replacing parts—it’s a precise adjustment of the balance spring’s effective length via Rolex’s Microstella system. A qualified watchmaker can fine-tune this to bring performance back within spec.

When accuracy changes suddenly or becomes erratic, that can signal magnetization, dried lubricants, or a need for full service. Rolex generally recommends servicing every 10 years, but heavy use or extreme environments can shorten that timeline. The good news: with proper care, many Rolex movements return from service running as precisely as the day they left Geneva.

When to Leave It Alone

Rolex Submariner on red rubber strap

A watch that runs slightly fast but does so consistently is still performing well. Many enthusiasts even prefer a small daily gain over a loss—it means the watch won’t fall behind schedule. The key metric is stability, not zero deviation.

Small timing differences are part of a mechanical watch’s personality. They remind you that the engine inside is entirely mechanical—no battery, no circuit, just gears, springs, and balance. Treat it well, store it carefully, and it’ll keep remarkable time for decades.