What drag clicking is
Drag clicking does not rely on how fast your finger can move up and down. Instead you press lightly on the mouse button and drag your fingertip along it. Friction makes the finger skip across the button, and each small bounce can register as a separate click. One drag can produce a whole burst of clicks.
This page uses the standard CPS test. Your first click inside the box starts a five second timer, every left click or tap counts, and the result shows your clicks per second to one decimal, a rating, your click count and your personal best.
Why your mouse and surface decide the result
With regular clicking, your finger sets the pace. With drag clicking, much of the work is done by the contact between your finger and the button. The texture of the button, the switch inside it and the condition of your fingertip all change how many bounces register. That is why drag clicking works well on some mice and barely at all on others.
If your drag score is close to your normal clicking score, the technique may not suit your mouse. That is not a skill problem, and more practice on the same mouse may not change it much.
Why drag click scores jump around
Drag scores are less steady than normal ones. A single good drag can add a large burst of clicks, and in a five second test every five extra clicks adds a full point to your CPS. One run might land in the average band and the next well into the fast bands, with no change in effort.
For a fair picture, look at your average in the Your scores panel rather than your single best run. The trend chart shows whether you are getting more consistent or just getting lucky now and then.
Drag clicking and mouse wear
Fast techniques add wear to mouse switches, and drag clicking puts the switch through a large number of presses in a short time. Over time a worn switch can start producing unwanted double clicks. If your mouse begins to act up, the mouse click test is a quick way to check the button.
You may also want to compare this technique with butterfly clicking, or measure your normal speed on the main CPS test so you know how much the drag really adds. Stop if your finger or wrist starts to ache.