SBGC251

The Grand Seiko Standard is a Seiko-exclusive accuracy standard for mechanical watches which has been established to ensure superior performance of Grand Seiko mechanical watches irrespective of the differences in environmental conditions in which a watch is used. The Grand Seiko Standard differs from the other recognised chronometer standards in two important respects. While most accuracy standard testing is done for five positions at two temperatures, the Grand Seiko Standard tests six positions at three temperatures. This is because the Grand Seiko Standard seeks to replicate real world conditions.

The accuracy of Grand Seiko differs according to the mechanism and caliber of your watch.
QUARTZ : The annual accuracy is ±10 seconds when worn on the wrist within a normal temperature range (between 5 ºC and 35 ºC) for approximately 8 hours per day.
SPRING DRIVE : Average monthly loss / gain is ±15 seconds when worn on the wrist within a normal temperature range (between 5 ºC and 35 ºC）.
MECHANICAL : Accuracy of Grand Seiko mechanical watches when worn is specified within the target range of -1 to +10 seconds per day. To properly judge the accuracy under normal use conditions, check the mean value of gain / loss over a period of seven to ten days.

As one of the very few fully integrated watch manufactures in the world, Grand Seiko possesses a mastery over the full breadth of the watchmaking process from the research and development of component materials to manufacture, assembly, adjustment, inspection and shipment.
— The Shizuku-Ishi Watch Studio produces world-class mechanical watches with highly accurate movements and exquisite exterior design
— The Shinshu Watch Studio drives innovative ideas and novel technologies behind the ultimate quartz watches and Seiko’s exclusive Spring Drive watches
Each of these pre-eminent watch studios plays a pivotal role in combining the cutting-edge technology and masterful craftsmanship necessary to reach the pinnacle of quality represented by Grand Seiko.
Click the button below to read more about Grand Seiko’s Shizuki-Ishi and Shinshu Watch Studios.