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Swiss Excellence Certified

The universally recognized
and independent label certifying
Swiss watchmaking excellence.

Since 1973, the COSC has subjected every timepiece to uncompromising testing to certify its utmost precision.

COSC, SWISS EXCELLENCE CERTIFIED

  • Number of certified movements in 2025
    2,1 million
  • Number of movements certified since the COSC's creation in 1973
    57 million
  • Percentage of mechanical watches exported in 2025 that are COSC-certified
    39%
  • Number of testing days
    12 to 20
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Over 60 brands are certified by the COSC.

Founded at the initiative of Swiss watch brands, the COSC dedicates its expertise and independence to certifying watches destined to join the watchmaking legend.

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From heritage to innovation

For over 50 years, our equipment and processes have continuously evolved to keep pace with the latest innovations in Swiss chronometry. As watchmakers push the boundaries by creating ever more innovative timekeepers, the COSC is doing the same for time measurement.

Behind the scenes of certification

COSC laboratory
woman working at COSC

How the COSC certifies precision in chronometry

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Discover our laboratories

Our three laboratories are equipped with cutting-edge equipment, custom-designed by our engineers to meet unique precision requirements. This equipment makes it possible to inspect more than 2 million movements and watches a year.

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