Key takeaways
- Measure to the wrist crease, not the palm base.
- Rest the hand flat and relaxed — no tensing, no stretching.
- Measure your mousing hand; length sets the class.
The right way to measure
Sit up straight. Rest your hand flat and relaxed on the desk — not curled, not stretched. Measure from the middle-fingertip to the wrist crease, the fold at the base of the palm (not the palm pad itself). Use a ruler or tape; a phone app works in a pinch.
Common mistakes that throw you off
Measuring to the palm base, not the wrist crease — the crease sits a bit lower; stop short and you under-report by a centimetre.
Tensing or stretching the hand — a stretched hand reads longer than your real playing hand. Relax it.
Measuring one hand only when they differ — most people have a dominant hand slightly larger; measure the one you mouse with.
Using width as length — width (across the knuckles) matters for shape, but size classes are built on length. Get length first.
Match the number to a size class
Once you have the length, map it: under 16.9cm → Small; 17–19.5cm → Medium; over 19.6cm → Large. One class off and the mouse you buy will either cramp your fingers or leave your palm with nowhere to rest. Measure once, honestly, and the rest of your mouse choice gets a lot easier.
| Mistake | Result | Fix |
|---|---|---|
| Measure to palm base | Under-reports length | Stop at wrist crease |
| Tense / stretch hand | Over-reports length | Relax flat on desk |
| Measure wrong hand | Wrong class | Measure your mousing hand |
| Use width as length | Mis-sized shape | Length sets the class |