MASTER
CHRONOMETER
Behind the elegance of every Master Chronometer timepiece is the highest level of testing: 8 tests over 10 days, to ensure superior precision and magnetic resistance. We’ve raised our standards. You can too.
DiscoverRAISING STANDARDS
DOUBLE CERTIFICATION:
METAS AND COSC
To own a MASTER CHRONOMETER is to be confident that your watch has been certified not once – but twice! The 8 stringent METAS tests your timepiece must face to earn the title MASTER CHRONOMETER can only begin with movements already certified by COSC (Official Swiss Chronometer Testing Institute). And it's a completely transparent testing process. If you want to know how your own watch performed during the 8 METAS tests, you can view the exact results by entering your certificate number online.
Discover the 8 tests
Twice as precise as any officially certified chronometer
Our Master Chronometer watches are tested and certified twice. Firstly, the movement is tested by the Official Swiss Chronometer Control (COSC) with precision criteria of -4/+6 seconds per day. Then the complete watch and its movement undergo eight Master Chronometer tests set by the Swiss Federal Institute of Metrology (METAS) with a pass criteria ranging from 0/+5 seconds to 0/+7 seconds per day, depending on the calibre type and size.
Proprietary anti-magnetic materials
Everyday items such as mobile phones, metal clasps on handbags, laptops, MRI, induction hobs or automatic doors; subject a watch to magnetic fields and can affect its performance for good. To prevent the risk of permanent deviations of up to several minutes a day we've conceived movements with antimagnetic materials, such as the silicon balance spring, capable of withstanding the highest fields.
Water-resistance
To ensure the integrity of our timepieces at depth, not just some but all watches are fully immersed in water and pressure is applied up to the point of the guaranteed water resistance. By submerging each watch in water we have chosen – yet again - to exceed normal testing standards.
Durability
Our watches are engineered to the highest standards and certified as such. Each watch destined to become a Master Chronometer must first pass 8 stringent tests. The examinations we perform for precision, magnetic-resistance, power reserve and water-resistance allow us to cover the certified watches with a comprehensive 5-year warranty.
Test N°1
Function of movement during magnetic exposure
This Master Chronometer test ensures your watch's movement is unaffected by magnetic fields from everyday items such as mobile phones, metal clasps on handbags, laptops, MRI, induction hobs and automatic doors.
Each movement is placed into a permanent "zero-energy-use" magnet and subjected to a strong magnetic field of 15,000 gauss.
Carefully-placed microphones monitor the ticking of the movements (tested in two different positions) to ensure their proper function in extreme magnetic conditions.
Test N°2
Function of complete watch during magnetic exposure
Once we've ensured the movement of your watch adheres to the anti-magnetic standards set by METAS, we then test the entire watch.
The movements are carefully assembled inside their cases and subjected to a further 15,000 gauss.
Microphones closely monitor the ticking of the complete watches to ensure they comply with METAS regulations.
Test N°3
Chronometric performance: magnetised and demagnetised
In order to prove your watch's worth in the real world, we subject it to multiple daily-use simulations. We begin this process with the following METAS test, which takes place over two 24-hour periods. (This test is integrated with the second stage of test 4)
Watches are rewound and fully magnetised in a field of 15,000 gauss.
At the start of day one a time 'stamp' is created by taking pictures of the watches hands and comparing their displayed times to an official METAS atomic clock.
After turning the watch heads in 6 different positions over a 24 hour period, a second set of pictures is taken to calculate the deviation between times displayed and atomic time.
On day two, the 24-hour testing process is identical to day one, only this time, the watches are demagnetised.
At the conclusion of the 48-hour test we calculate deviations between the magnetised and demagnetised results to ensure there's no impact on precision and our watches fall within the strict tolerances set by METAS.
Test N°4
Chronometric precision day-to-day
Everything from wave of a hand to Earth's gravity can have an impact on a watch's performance, so to simulate daily conditions on and off the wrist we test our watches at two different temperatures, under extreme magnetism and in six different positions. These METAS tests are carried out over four 24-hour periods.
Each day the watches are rewound and subjected to the following tests:
On wrist:
14 hours at 33 degrees Celsius with watches turned to different positions every 3 hours
Off wrist:
10 hours at 23 degrees Celsius with watches turned to different positions every 5 hours
Results on the precision of the watches (see test 3 procedures) are recorded daily and used at the completion of the 4 x 24-hour testing period to calculate the daily average deviation of each watch against a METAS-provided atomic clock.
Only the minutest deviations in these daily averages are permitted for a watch to become a Master Chronometer: Just 0-5 seconds per day or a maximum deviation of 0.0058% over a 24-hour period (half that of COSC).
Test N°5
Deviation of chronometric precision in six positions
Life is dynamic. You're always on the move. So for this acoustic test, each watch is placed in six different positions to verify your watch stays precise at any angle. The positions are changed every 60 seconds.
Carefully positioned microphones register the ticking of the movements to calculate the precision of the watches.
Out of these six results, we establish the deviation between the two most extreme results known as the Delta, to ensure the movements are METAS compliant.
Test N°6
Isochronism
Setting your watch aside for a period of time stops it from winding automatically and can affect precision. To ensure it still keeps the right pace at low power, we test the watches acoustically in 6 different positions at 100% power reserve and 33% power reserve.
The watches are fully wound so the power reserve is at 100% (for example 60 hours).
Microphones register the ticking of the movements in six different positions in order to calculate precision.
The watches are left running until their power reserves reach 33% (for example 40 hours later).
Again, the movements are acoustically tested in six different positions.
We then take the average results of the measured precision during both states of the power reserve. The deviation between the two must fall within the tolerances set by METAS.
Test N°7
Power reserve testing
The power reserve is the difference between the fully wound watch and the moment it stops working. As you won't always be wearing your OMEGA (you may leave it at home for the weekend for example) it's important it continues to function at the limit of its expected capacity.
The watches are fully wound (power reserve at 100%).
The start time for the test is then recorded by photographing the position of the watch hands and comparing the reading to atomic time.
The watches are then left to function for the duration of their promised power reserve (e.g. 60 hours) before further pictures of the hands are taken to make a second atomic time comparison.
These readings must adhere to the power reserve standards set by METAS.
Test N°8
Water resistance
The purpose of this final METAS test is to prove that your watch complies with its stated water resistance.
Watches are submerged in a water tank and pressurized; for minutes or many hours, and pushed to their limits at pressures from 3 bar (30m) to 150 bar (1500m) - depending on the watch.
Once taken out of the water, each watch is heated to reach a temperature between 40 and 45 degrees Celsius.
A drop of cold water is then placed on the sapphire glass of each watch by hand. If condensation appears, it shows that the watch does not comply with METAS standards.
NOTE: In order to ensure added safety and security for professional divers, the pressure is actually raised 25% higher than the stated water-resistance when testing divers' watches.