Keyboard Glossary
Search and filter the vocabulary used in group buys, build guides and vendor spec sheets, with links to the tools that apply each concept.
Tool Operation Area
30 entries
- 1uKeycaps
- One key unit, the 19.05 mm grid pitch every MX-compatible board is built on. Key widths are quoted as multiples of it, such as a 6.25u spacebar. Apply this with the related tool →
- Actuation pointSwitches
- The depth at which a keypress registers, typically 2.0 mm on a standard MX switch and around 1.1 mm on a speed switch. Apply this with the related tool →
- Bottom-out forceSwitches
- The spring load when the stem reaches the bottom housing. Most vendor gram ratings on marketing pages refer to this figure, not to actuation force. Apply this with the related tool →
- Case foamTuning
- A foam layer between the PCB and the case floor that removes air volume and kills the hollow reverberation in each keystroke. Apply this with the related tool →
- ChatterPCB & Firmware
- A single keypress registering twice, caused by contact wear, a partially seated switch or firmware debounce set too low. Apply this with the related tool →
- Coiled cableCase & Mounting
- A cable with a helical section, largely aesthetic. The coil consumes usable length and should be excluded from reach calculations. Apply this with the related tool →
- DaughterboardPCB & Firmware
- A small separate board carrying the USB port, connected to the main PCB by a ribbon cable so port stress does not reach the main board.
- DebouncePCB & Firmware
- A firmware delay that ignores rapid repeat contacts after a keypress so mechanical bounce does not register as multiple presses. Apply this with the related tool →
- Flex cutsPCB & Firmware
- Slots milled into a PCB between switch rows to increase downward flex, producing a softer typing feel at the cost of rigidity. Apply this with the related tool →
- Gasket mountCase & Mounting
- A mounting style where the plate is suspended between compliant gasket strips instead of screwed rigidly, giving a softer, more cushioned typing feel.
- Group buyCase & Mounting
- A pre-order model where a run of a kit is manufactured only after enough units are committed, often with long lead times. Apply this with the related tool →
- Holee modTuning
- Wrapping a stabilizer wire in a thin strip of fabric bandage to remove lateral rattle inside the stem housing. Apply this with the related tool →
- Hot-swap socketPCB & Firmware
- A surface-mount clip soldered under the PCB that grips a switch pin, allowing switches to be changed without soldering. Apply this with the related tool →
- Krytox 205g0Tuning
- A thick PFPE grease that is the community default for lubricating linear switch stems and housings. Apply this with the related tool →
- LinearSwitches
- A switch with a smooth force curve and no tactile bump or click mechanism through the whole travel. Apply this with the related tool →
- Pin clippingSwitches
- Trimming the two plastic alignment legs from a 5-pin switch so it fits a 3-pin PCB. Apply this with the related tool →
- PlateCase & Mounting
- The sheet between switches and PCB that holds switch housings in place. Material and thickness change stiffness and sound significantly. Apply this with the related tool →
- Plate foamTuning
- A thin foam layer between plate and PCB, usually 1 to 1.5 mm, that damps plate ringing at the cost of some flex. Apply this with the related tool →
- Polycarbonate (PC)Switches
- A hard, translucent housing material that reflects high frequencies, giving a brighter and higher-pitched sound signature.
- POMSwitches
- Polyoxymethylene, a self-lubricating plastic used for switch stems and some housings. Naturally smooth and deep sounding. Apply this with the related tool →
- ProfileKeycaps
- The height and shape family of a keycap set, such as Cherry, OEM, SA, DSA or XDA. Sculpted profiles vary by row; uniform profiles do not. Apply this with the related tool →
- QMKPCB & Firmware
- Open-source keyboard firmware used by most custom PCBs, supporting layers, macros and full key remapping.
- Screw-in stabilizerTuning
- A stabilizer housing fastened to the PCB with a screw, which is more stable and more tunable than a snap-in or plate-mount unit. Apply this with the related tool →
- StabilizerTuning
- A wire-and-housing mechanism that keeps wide keys such as the spacebar and enter level across their width. Apply this with the related tool →
- Stepped caps lockKeycaps
- A caps lock keycap with a raised step on part of its surface, used on some vintage-inspired layouts and rarely included in base kits. Apply this with the related tool →
- Tactile bumpSwitches
- A localised increase in force partway through travel that signals actuation to your finger without any audible click. Apply this with the related tool →
- ThockTuning
- Community shorthand for a deep, low-pitched bottom-out sound, typically produced by nylon housings, PBT caps and generous case foam.
- Top mountCase & Mounting
- A mounting style where the plate is screwed to the upper case half, producing a firm and uniform typing feel.
- Tray mountCase & Mounting
- A mounting style where the PCB screws directly to posts in the case floor, the cheapest approach and the least uniform in feel.
- VIAPCB & Firmware
- A configuration layer on top of QMK that lets you remap keys live in a browser or app without recompiling firmware.
Working Principle
Custom keyboard terminology is a mix of manufacturing vocabulary, community shorthand and product names, which is why newcomers find spec sheets impenetrable. The glossary organises terms by the part of the build they belong to: case and mounting, PCB and electronics, switches, keycaps, and tuning. Mounting terms in particular describe a real mechanical difference. Tray mount screws the PCB to posts in the case floor, which creates stiff points at each screw and softer areas between them. Top mount clamps the plate to the upper case half, producing a firmer, more uniform feel. Gasket mount suspends the plate on compliant strips so it can move slightly under keystrokes, which is why gasket boards are described as softer. Electronics terms such as QMK and VIA describe firmware: QMK is the open-source firmware many custom PCBs run, and VIA is a configuration layer that lets you remap keys without recompiling. Switch terminology divides by feedback type — linear, tactile and clicky — and by construction details such as the stem material and whether the housing is nylon, polycarbonate or a blend, each of which changes the sound. Definitions here are written to be understood without prior knowledge, and each term points to the calculator or checker on this site where the concept has practical consequences.
How to Use
- 01Type any term or part of a definition into the search field.
- 02Filter by category to browse a whole area, such as mounting styles or switch terms.
- 03Follow the linked tool on any entry to apply the concept.
- 04Tip for beginners: read the mounting and switch categories end to end before your first group buy.
FAQ
How current is the terminology?
Entries cover the vocabulary in general use across vendor listings and build guides. Product-specific slang from individual communities is intentionally excluded.
Why do some definitions disagree with a vendor page?
Vendors sometimes use marketing names for standard concepts. Where that happens, the entry describes the underlying mechanical reality.
Can I use this offline?
Yes. The entire glossary ships with the page and needs no network request after load.
Is there an ordering to learn these in?
Start with layout and mounting, then switches, then tuning. That sequence matches the order decisions are made in a build.
Related Tools
Switch Parameter Database
Filter mainstream linear, tactile and clicky switches by force, travel and sound.
Build Troubleshooter
Diagnose chatter, dead keys, stabilizer rattle and crooked switches.
Switch Compatibility Checker
Verify switch, socket and plate cutout compatibility before you order.
Keyboard Layout Size Calculator
Get PCB footprint, key count and case margins for any layout.