Cherry MX Blue, Brown, Red and Green stems with their return springs. Photo: Cherry MX -- stems and springs.jpg, Daniel beardsmore · Public domain dedication by author. Resized with ivory padding.
The switch beneath a keycap determines much of what you feel when you press it. Three common types give you different feedback: linear switches have no deliberate bump, tactile switches add a bump, and clicky switches add an audible click.
For a fidget, compare the feel of the press, the effort it takes and the sound of the complete movement.
Linear: a press without a bump
A linear switch moves without a designed tactile bump. The spring still provides resistance, and different models can need different amounts of force.
CHERRY's MX Speed Silver, for example, has linear movement, no designed click and 3.4 mm of total travel. The full model name matters because another linear switch may have a different spring or travel distance.
Try the full press and release. If you like an uninterrupted movement, a linear switch is worth comparing with the other types. If you prefer a distinct response partway down, try a tactile switch.
Tactile: a bump you can feel
A tactile switch has a deliberate change in resistance during the press. The size and position of that bump vary between models.
A bump doesn't require a click. CHERRY lists its MX Brown as tactile with no click. Describe the bump and the spring resistance separately when comparing switches; either could be the part you find too firm.
Ask for the brand and full model name. Switch colors don't reliably mean the same thing across manufacturers.
Clicky: tactile feedback with an audible click
A clicky switch deliberately produces a click as part of the action. CHERRY's MX Green, for example, combines tactile feedback with a click.
If you enjoy that sound, listen to several repetitions at the pace you'd use the toy. Consider whether the sound suits the room as well as your preference.
Switches without a designed click can still make noise. CHERRY's MX Silent Red uses damping to reduce operating noise. For a finished fidget, listen to the whole press and release; the switch label doesn't describe every sound the toy makes.
Choose the complete toy
The keycap and holder matter too. Does your thumb rest comfortably on the cap? Does the holder stay steady? Is releasing the button as comfortable as pressing it?
Our Mechanical Keycap Fidgets and Dumpling Clicker Keychain offer different shapes to consider, with their own listed mechanisms. The CHERRY examples above explain switch types; they aren't specifications for these shop listings.
If you plan to change parts, check that the holder accepts the replacement switch and keycap, and that the maker intends them to be removable. A favorite switch in an awkward holder still makes an awkward fidget. Choose the part your thumb rests on as deliberately as the part beneath it.