Amplitude

Amplitude describes how far the head of a percussion massager moves back and forth with every stroke, usually measured in millimeters. It is a separate spec from speed, which measures how many times per minute the head strokes, and from stall force, which measures how much pressure the motor can push against. A gun can be fast but still feel shallow if its amplitude is short.

Most consumer massage guns fall somewhere between 10 and 16 millimeters. Shorter amplitude tends to feel gentler and more like a buzzing vibration, which suits sensitive areas, smaller muscles or anyone new to percussion massage. Longer amplitude reaches deeper into muscle tissue and is generally preferred by athletes or anyone who wants firmer, more noticeable pressure on large muscle groups like the hamstrings or back.

When comparing models, amplitude is worth checking alongside stall force rather than on its own, since a long amplitude gun with weak stall force can still stall out under real pressure. A common misconception is that a higher number is always better, in practice the right amplitude depends on the area being treated and personal comfort, and starting on a shorter setting before working up to deeper pressure is a sensible way to avoid soreness the next day.