Watch Accuracy Guides
Everything you need to understand, measure, and improve the timekeeping of a mechanical watch — written to answer the questions collectors actually ask.
How Accurate Should a Mechanical Watch Be?
Normal daily rates, what COSC / METAS / Superlative certification actually guarantees, and when poor accuracy means a service is due.
How to Measure Watch Accuracy at Home
Three ways to get a trustworthy seconds-per-day number — from a free manual method to listening to the movement itself.
Why Is My Watch Running Fast or Slow?
Magnetism, service wear, and position effects: how to tell which one your watch has and what to do about it.
What Is a Timegrapher? Readings Explained
Rate, amplitude, and beat error — what each reading means, healthy ranges, and hardware vs. app accuracy.
Watch Accuracy by Brand: Rolex, Omega, Seiko
Published accuracy specs by brand and movement tier, and what owners actually measure in practice.
Beat Error Explained
What the tick-tock asymmetry means, acceptable ranges by movement, and whether it can be fixed at home.
Building a Timegrapher From a Phone Microphone
The engineering deep-dive: epoch folding, autocorrelation, and how a phone mic hears a watch escapement.
Watch Accuracy Reports — How to Read Them
What ChronoLog accuracy reports show and how to interpret the numbers.