A Jumping Hour is a watch complication where the hour is displayed through a digital aperture, typically located on the dial, and changes instantaneously at the top of each hour. Unlike traditional analog watches where the hour hand gradually moves around the dial, a Jumping Hour watch features a disc with printed numbers that jumps to the next hour precisely when the minute hand reaches the 60-minute mark. This mechanism provides a unique and precise way of reading the time, offering a clear and immediate indication of the current hour.

The Jumping Hour complication is often paired with a traditional minute hand, allowing for a blend of digital and analog time-telling. This design is appreciated for its mechanical complexity and the visual interest it adds to a watch. The mechanism requires precise engineering to ensure the hour disc jumps accurately and reliably, making it a testament to the watchmaker's skill.

Jumping Hour watches are valued for their distinctive aesthetic and the technical challenge they present. They are often found in high-end and luxury timepieces, appealing to collectors and enthusiasts who appreciate the innovation and craftsmanship involved in their creation.