KEYCAP

A keycap is the removable cover that sits on top of a keyboard switch. It forms the visible label for the key and contributes to the typing feel and sound. Most commonly, keycaps are mounted on a standardized stem and can be exchanged without replacing the switch.

Keycaps are usually made of plastic. The two most common materials are ABS (acrylonitrile butadiene styrene) and PBT (polybutylene terephthalate). ABS caps are inexpensive and can produce sharp legends but tend to develop a shiny patina with use. PBT caps resist shine and often have a grainy or textured feel, but may be more prone to color dye bleed in certain colorways.

Keycaps come in different profiles, which define their height and shape across rows. Common profiles include OEM and Cherry, with sculpted variants such as SA, MT3, and XDA. The chosen profile affects typing rhythm and aesthetics. Most modern keyboards use MX-style cross-shaped stems, ensuring broad compatibility among aftermarket caps.

Legends on keycaps can be created by various methods. Dye-sublimation and doubleshot molding offer durable legends; pad printing and laser etching are more economical but can wear over time. Some caps are unetched and rely on translucency for backlighting.

Sizing and stabilization: keycaps come in standard widths such as 1U and larger variants for wide keys. Stabilizers are used on longer keys to reduce wobble. Keycaps are widely compatible across mechanical keyboards, but non-standard layouts or different switch stems can limit interchangeability. Maintenance includes regular cleaning and avoiding harsh chemicals; many users clean with mild soap and water or isopropyl alcohol while caps are removed. The concept of keycaps dates to typewriter-like keyboards, with aftermarket customization gaining prominence alongside mechanical keyboards since the 1990s.