Where the keyboard and mouse go

Most keyboard advice is about wrists. Keep them straight, don’t rest them on the edge, consider a split keyboard.

Wrists are worth getting right, and they’re not where the biggest effect is. The biggest effect is reach — how far forward and how far sideways your hands have to travel from where your arms naturally hang. Reach is what determines whether your shoulders can stay down, and shoulders are what most people actually feel by the end of the day.

This comes after the chair and the monitor, because both change where your hands end up.

The reach check

REACH — the check
  Sit back fully against the backrest. Let both arms hang straight down.
  Now bend your elbows and bring your hands to the keyboard and mouse
  WITHOUT moving your torso or lifting your shoulders.

  · Both hands land where they need to be        → reach is right
  · You have to lean forward to reach            → too far away
  · You have to extend your elbow to reach the
    mouse, or your shoulder rotates outward      → mouse is too far to the side
  · Your elbows go behind your torso             → too close

The instruction that does the work is without moving your torso. Almost everyone, told to reach for their keyboard, will lean slightly and not notice. Press your back into the backrest first and keep it there.

If you fail this check, you have your answer, and it’s usually one of two things.

Why the mouse ends up too far away

The single most common input problem, and it’s caused by a design decision nobody made deliberately.

A full-size keyboard has a number pad on the right. The number pad is typically a hundred millimetres or so of keys that most people use rarely, and it sits between your right hand and your mouse. So your mouse lives that much further out, and every time you use it your right arm abducts — moves away from your side — and your shoulder works to hold it there.

That’s a small load held for hours, on one side only. It’s why right shoulder and right neck complaints are so much more common than left among desk workers, and it’s a furniture problem with a furniture fix.

Three ways out, cheapest first:

Move the keyboard left. Free, immediate, and it feels wrong for about a day. Centre the letter portion of the keyboard on your body rather than the whole slab, letting the number pad hang out to the right. Your typing hands end up correctly placed and the mouse comes in. If you use the number pad occasionally, you reach for it occasionally, which is the right trade.

Use a keyboard without a number pad. A tenkeyless or compact board removes the problem structurally. A separate number pad can live on the left if you need one.

Move the mouse to the left hand. Works, takes a couple of weeks to stop being annoying, and distributes the load. Worth knowing as an option; not necessary for most people.

The first one costs nothing and solves most of it.

Distance, and what pushes it out

The keyboard wants to be close enough that your upper arms stay near your sides. What pushes it away:

Palm rests and thick keyboard fronts occupy desk depth in front of the keys. A palm rest is meant to support your palms between bouts of typing, and people instead use them to rest on continuously while typing, which pins the wrist and makes the fingers do all the travel.

Armrests too high, which stop you pulling the chair fully under the desk. If the chair can’t come in, the keyboard has to come out.

Clutter along the front edge of the desk. Habitual, invisible, and it silently sets your minimum reach.

Laptop screens, unavoidably — the screen is attached to the keyboard, so putting one at a good distance puts the other in the wrong place. That’s a problem of its own.

There should be room in front of the keyboard to rest your hands or forearms when you’re not typing. Not to type from — to rest.

Wrist angles, briefly

Now the wrists, which do matter, in three axes.

Up and down. Your wrist should be roughly flat, not cocked upward. A cocked wrist usually means the keyboard is too high relative to your seated elbows — a chair problem — or the keyboard’s own back legs are flipped up. Which brings us to:

The little flip-out feet on the back of every keyboard tilt it the wrong way. They raise the far edge, which forces your wrists into more extension. They exist because they make the key legends easier to see, which matters if you look at the keys. If you don’t, fold them down. A slight negative tilt — far edge lower — is what suits typing without looking, and you can approximate it by putting something thin under the near edge.

Side to side. Your hands should point roughly straight ahead, not angled outward at the wrist. Standard keyboards force some of this by being flat and narrow; the fix is either to move the keyboard further from your body slightly, letting your forearms converge less, or to use a keyboard that splits or tents. This is where a purchase genuinely helps, and it’s optional.

Rotation. Palms flat down is a slightly rotated forearm position. Some people find a tented keyboard — inner edges raised — noticeably more comfortable. Others notice nothing. Try it before spending anything by propping the inner edges of a split keyboard, if you have one.

The mouse itself

Grip. If you’re pinching the mouse to control it, it’s too small for your hand or too light. Gripping continuously is a real load on the forearm. A larger mouse, or simply loosening the grip deliberately for a few days, fixes most of it.

Sensitivity. Low sensitivity means large arm movements for small cursor movements — the mouse travels further, and your shoulder does the work. Raising the pointer speed so the cursor crosses the screen with a wrist-scale movement rather than an arm-scale one reduces total travel substantially, costs nothing, and takes a day to adapt to. This is one of the highest-value changes on this page and it isn’t a furniture change at all.

Same surface as the keyboard. A mouse on a different level than the keyboard means your two arms are at two heights. Common with pull-out keyboard trays that aren’t wide enough for a mouse; if that’s your setup, the tray is too narrow and the keyboard is better off on the desk.

Two things that aren’t real problems

Resting your wrists on the desk edge while typing gets warned about constantly. Resting between bursts is fine and normal. Resting continuously while typing is the thing to avoid, because it pins your hand and forces finger-only movement. The distinction is what you’re doing, not whether contact happens.

Mechanical versus membrane keyboards has approximately nothing to do with any of this. Key feel is a preference. Position is the variable that matters.

When it still isn’t right

If reach is correct, wrists are neutral, and you still get forearm or hand symptoms, the remaining variables are how much you type and how hard. Neither is a furniture setting.

And the standing note: numbness, tingling, or weakness in the hands — especially at night or in a specific finger pattern — is a reason to see a clinician rather than to keep rearranging the desk.