Choosing a keyboard wrist rest size is easier when you start with a ruler. Layout labels such as TKL, 75% or full-size tell you about the keys on a board, but the case around those keys can change its width and profile.
The Wrist Rest offers two keyboard-rest widths: 360 mm and 440 mm. This guide helps you compare those options with your own board, rather than assume a layout name guarantees a match.
The three measurements to take
1. Keyboard width
Measure the keyboard case from left edge to right edge. Include the bezel, but do not count a cable extending beyond it. Record the result in millimetres so you can compare it directly with the rest’s listed width.
If your keyboard has an unusual shape, note that too. A rectangular rest might match its overall width while leaving gaps beside a curved front edge.
2. Front-edge height
Measure from the surface beneath your keyboard to the front of its case. Keep the keyboard in the position you normally use, including any mat underneath it. Note its slope as well: a width match does not settle the height question.
OSHA recommends choosing wrist/palm supports to suit the keyboard’s front-edge dimensions and slope. It also advises keeping hands free to move while typing. Read OSHA’s support guidance.
3. Available desk space
Measure the space in front of the keyboard and beside the mouse. Consider whether a rest would crowd another item or leave you reaching over it. You are fitting an accessory into a working desk, not just matching two numbers on a product page.
Compare 360 mm and 440 mm
| Option | Listed width | Useful starting point | What to verify |
|---|---|---|---|
| Medium keyboard rest | 360 mm / 36 cm | A narrower keyboard or compact desk | Your actual case width and hand positions |
| Large keyboard rest | 440 mm / 44 cm | A wider keyboard, often with a number pad | Case width and space beside the mouse |
These starting points are not a model-specific compatibility list. Compare both keyboard wrist rest sizes.
Work out the width difference
Subtract the keyboard width from the rest width. If both are centred, half that difference will sit on each side.
For example, a 360 mm rest is 10 mm wider than a hypothetical 350 mm board. Centred together, that is 5 mm of extra width on each side. A 440 mm rest is 15 mm shorter than a hypothetical 455 mm board, leaving 7.5 mm of keyboard beyond each end.
Those are arithmetic examples, not endorsements of either pairing. They help you picture the alignment before deciding how the rest would meet your hands during pauses.
Does a TKL or 75% keyboard need the smaller size?
Use the smaller option as a candidate, then check the case measurements. Layout names describe key arrangements; product cases are not all identical.
The same rule applies to a mechanical keyboard wrist rest. “Mechanical” identifies the keyboard technology, not one standardized width or height. Check the particular keyboard model and the dimensions of the accessory you want to buy.
For a split board, compare the support with the positions of both halves. A long straight rest may be inconvenient if you prefer widely separated or angled halves.
Check the 20 mm profile separately
The Wrist Rest homepage lists a 20 mm height for the range. That is a product specification, not a recommended height for every keyboard. A slim board and a taller case can present different fit questions even when their widths are similar.
Evaluate the combined setup from the side. During a pause, notice whether the support puts your hand in a position that feels forced. Reposition or remove it if it makes the arrangement less comfortable. See the existing keyboard fit guide for the wider setup considerations.
Questions before ordering
Should the rest be exactly as wide as my keyboard?
A close width match can make alignment straightforward, but assess where your hands land and how much desk space you have. Width alone does not establish suitability.
Does a larger rest provide better support?
A larger footprint is not automatically a better fit. It may occupy space you need for your mouse or another desk accessory.
Is the mouse rest included?
The individual keyboard product contains one keyboard rest. The keyboard and mouse rest set combines your chosen keyboard width with a 150 mm mouse rest.
Will the correct size treat carpal tunnel?
Sizing an accessory is a comfort and fit decision. It does not establish a treatment benefit. For carpal tunnel concerns, read the keyboard-rest guide and discuss persistent symptoms with a qualified clinician.
Keep a short measurement note
Before choosing, write down your keyboard width, front-edge height and available desk space. Then compare the 360 mm and 440 mm memory foam keyboard rests. Those three measurements make the choice more specific than a layout label or product photograph.