Vibrations per Hour (VPH) is a critical metric in horology that quantifies the frequency at which a watch's balance wheel oscillates. This measurement is pivotal in determining the precision and accuracy of a mechanical watch. The balance wheel, a crucial component of the watch's movement, swings back and forth, and each complete swing is counted as one vibration. VPH is calculated by multiplying the number of vibrations per second by 3,600, the number of seconds in an hour.

A higher VPH generally indicates a more accurate timepiece, as it allows for finer regulation and less susceptibility to external disturbances. Common VPH values in modern watches range from 18,000 to 36,000. For instance, a watch with a VPH of 28,800, which equates to 8 beats per second, is considered to have a high frequency, offering a good balance between precision and durability. However, higher VPH can also lead to increased wear and tear on the movement components due to the faster oscillation rate.

In summary, VPH is a fundamental aspect of watchmaking that influences the timekeeping performance and longevity of a watch, making it a key consideration for both watchmakers and enthusiasts.