For large hands, buy the Logitech MX Master 4— at 5.05 x 3.48 x 2.0 in it is the biggest shell here and the only one that fills a long palm without a stretch to the buttons. For small to medium hands, buy the Logitech Lift, which Logitech itself sizes for small and medium hands and sells in a left-handed version. If you are between the two, or you have tried both and neither fitted, the Logitech ERGO M575S trackball is the format where hand size largely stops mattering.
Hand size is the least discussed and most decisive spec in a mouse. Grip style follows from it: a shell that is too short for your palm pushes you into a claw grip, where the fingers arch and the wrist extends, and a shell that is too large keeps your fingertips reaching for buttons that should be under them. Neither is a disaster for an hour. Both are a problem across a working day.
Measure your hand first
Two numbers, taken on a flat surface with your hand open and relaxed. Hand length is the distance from the base of your palm — the crease at your wrist — to the tip of your middle finger. Hand width is across the palm at the knuckles, excluding the thumb.
Then match roughly. A palm-grip mouse wants a shell about three quarters of your hand length, so the heel of your hand rests on the back of the mouse while your fingertips sit on the buttons. Shorter than that and your palm floats; longer and you are pushing the mouse from the middle of your hand. This is the same reasoning that makes a narrower keyboard more comfortable: it is about where your joints end up, not about the device.
The published numbers are not all equal
Logitech publishes exact dimensions and weights for its MX line, and we have used them. For the Lift and the Evoluent VerticalMouse 4, the makers publish a stated hand-size fit rather than a shell measurement, so that is what the specs below say — the manufacturer’s claim, labelled as such. We have not converted one into the other, and we have not measured any of these shells ourselves, because we do not have a lab and are not going to pretend otherwise.
Vertical mice change the question
A vertical mouse rotates your forearm out of pronation, and that changes which dimension matters: height and the angle become as important as length. Logitech builds two at the same 57-degree angle in two shell sizes — the MX Vertical, which it describes as suiting medium to large hands, and the Lift, sized for small to medium. That pair is the clearest same-design, two-sizes comparison available, which is why both are below. The full vertical mouse roundup ranks the format on its own terms.
And a trackball ignores it
On a trackball, the device does not move and your arm does not either. Shell size still affects where your fingers land, but the reach-and-drag problem that makes a badly sized mouse hurt simply is not present. If you have replaced two mice and still have a sore wrist, that is the honest next thing to try — and our vertical mouse versus trackball comparison explains which complaint each format actually addresses.
The shells, by the published numbers
| Mouse | Published size | Weight | Stated hand fit |
|---|
| MX Master 4 | 5.05 x 3.48 x 2.0 in | 150 g | Not stated; largest shell here |
| MX Master 3S | 4.92 x 3.32 x 2.01 in | 141 g | Not stated; second largest |
| MX Vertical | 4.72 x 3.11 x 3.09 in | 125 g | Medium to large (Logitech) |
| Logitech Lift | Not published | Not published | Small to medium (Logitech) |
| ERGO M575S | Not published | Not published | Trackball - hand does not travel |
The blanks are deliberate. Logitech publishes full dimensions for the MX line and a stated hand-size fit for the Lift, and we are not going to fill the gaps with numbers lifted from a retailer listing. If an exact shell height decides your purchase, a store with a return window is a better test than any spec sheet.
Which to buy, by hand length
Long hand, palm grip, conventional shape. MX Master 4, or the 3S to save money. The 4 is larger in every dimension; the difference is small on paper and noticeable in the hand.
Long hand, wrist or forearm complaint. MX Vertical. The 3.09 in height is the spec that makes a vertical work for a big hand, and nothing else here is close to it.
Small hand. Logitech Lift, and the left-handed version if you are left-handed. It is the only pick on this page that exists in both.
Hand size is not really the problem.ERGO M575S. If two correctly sized mice have both ached, the thing to change is how much your arm moves, not how big the shell is — the trackball roundup goes deeper, and the ergonomic mouse roundup covers the field by complaint rather than by size.
Two things that undo a correctly sized mouse
A full-size keyboard. The number pad pushes your mouse hand out past your shoulder, and the resulting reach produces exactly the shoulder and neck ache people blame on the mouse. A tenkeyless or 75% board is the fix, and the ergonomics guide has the geometry.
A desk that is too high. If your elbow sits below the desk surface, your wrist extends to reach the mouse whatever shell you bought. Check the desk height guide, and if the desk cannot move, drop the input devices instead with an under-desk keyboard tray - most trays carry the mouse as well as the board.
