In the last blog<Exploring Different Types of Keycaps>, we explored different types of keycaps in the aspects of material and legend process. Today we are going to dive deeper about the keycap size, layout and profiles.
To update a keyboard with a compatible keycap set, we need to figure out the keycap layout and size first. Otherwise, when we get a new set of mech keyboard keycaps, surprisingly find the keys are not in the same size with the keyboard. Or surprisingly find some key missing in the keycap set. What a pity it is!
Keycap Layout
As same as keyboard layout, there is also 75 keyboard keycaps, 65 keycaps, or numpad keycaps in the market. If we are not using a full size keyboard, then if there is no need to purchase a full size keycap set, which can save money and avoid the waste of other extra keycaps.
For different layout mechanical keyboard keycap, the spacebar keycap of 40% keyboard might be divided into 2u+2u keys, or 3u+3u keys. And the Alice spacebar keycap are different in the left and right part, normally 2.25~3u.
And we need to make sure whether the keycaps sets support ANSI or ISO keyboard layout. For ANSI keycap set, there would be 2.25u Enterkey, 2.25u left shift key and 2u backspace key. However, for ISO layout keyboard keycap, those keys are totally different. There exits a 2.75u Enter key, 1.25u left shift key and 1u+1u backspace key.
Keycap Size
The dimensions of mechanical keyboards keycaps are uniformly expressed using "u" (unit). 1u is approximately equal to the width of a standard letter key, which is approximately 19.05mm.
Common Size
| Keys | size(u) |
| Number key, Letter key | 1u, A~Z / 1~0 |
| Function key | 1u / 1.25u, keys like ESC, F1~F12, Del, PgUp |
| Tab | 1.5u |
| CapsLock | 1.75u |
| Shift | 2u/2.25u / 2.75u |
| Enter | 2.25u / 2.75u, ANSI (2.25u), ISO (2.75u) |
| Backspace | 2u (ANSI) , 1u+1u(ISO) |
| Space | 6u / 6.25u / 7u |
| Ctrl / Al | 1.25u / 1.5u |
Before Purchasing:
1、check the size of keys above
2、For most budget keyboard, we can choose 6.25u spacebar with ANSI layout keycap set.
3、For custom keyboard keycaps, it is usually full compatibility with 7u spacebar keycap or some extra replacement keycaps.
4、Using unmatched keycaps forcibly will cause stabilizer bar stuck or broken, the MX stem of the switch damaged, deformed or cracked keycaps.
I define the keycap size and layout as the most important step of choosing a keycap set. If we come across a satisfying keycap set, which can meet all the requirements, like material, price. But the keycap size is not suitable, all the rest are of no use.
Keycap Row
Before introducing the keycap profile, there is another feature about keycap set we need to know in advance. That’s the row of keycaps.
The height of each row is different, which form a unique slope for different profile. The reasonable slope design is aimed at enabling fingers to type the keys of different rows in a naturally bent position, thereby reducing wrist fatigue.
The keycaps mechanical keyboard normally owns 6 rows from the row of function key to the row of spacebar key. The standard slope is that the middle row (such as the letter area) has the lowest height, and gradually increases towards the top and bottom (the spacebar row is the highest or the function row is the highest). While we hardly call them from R1 to R6, starting from the function row to spacebar row, it is R1-R1-R2-R3-R4-R4. Some manufacturer also range them R4-R4-R3-R2-R1-R1. See the image below.
Keycap Row Shape
Uniform keycap shape
The keycaps in the different row are at the same shape and height. If we want a flat typing feeling, we can choose uniform keycap shape, like XDA and DSA profile.
Sculpted Keycap shape
While for most keycap shape, like Cherry keycap, OEM keycap or Sa keycap, we can see the different height between each row. It is designed to provide a more comfortable typing feeling with ergonomic angle.
image from reddit
Keycap Profile
keycap types differ in keycap shape and height. Many manufacturer design various types of keycaps. But there is no standard naming rule for keycap profiles. They are named by the manufacturer, like Cherry Profile.
The profile of the keycaps is one of the core factors that affect the keyboard's feel, ergonomic comfort, sound performance and visual style. Different profile types have distinct characteristics. That’s why it’s important to choose the right type of keycap profile which is best for us. Here is a classification, comparison and purchase guide for the mainstream keycap profiles.
Cherry Profile
Germany-based Cherry makes standards for cherry profile keycaps, featuring low ball shaped caps (with the top slightly concave to fit the fingertips), with a small height difference and a gentle slope.
Suits for: long time typing, and less mistyping. It matches with all the MX switches mechanical keyboard.
OEM Profile
OEM keycaps are quite similar with Cherry mx keycaps. But there is larger height difference and a steeper slope in the oem keycaps. OEM is also one of the keycap profiles widely used in the pre-built mechanical keyboards. It suits for gamer, or limited budget starter.
SA Profile
SA keycaps are the representative of ball keycaps. Ultra-high cap and deep indentation on the surface makes a retro cylindrical shape, also distinct hollow sound in the keycaps. If we persuit a retro keyboard appearance, sa profile keycaps can meet the need.
The shape is relatively round. Since there is large concave arc of the sa keycap profile, and the surface area where the finger contacts the keycap is relatively small. Without using a hand rest, our hands might get tired for long time typing.
Image from Kzzi Z98 KSA keycap profile, not SA profile
DSA keycap profile
dsa profile keycaps are popular for its relatively low profile height and round shape. It maintains a flat height in each row. The comfortable and consistent typing feeling is favored by both typist and gamer. The dsa keycaps usually provide a minimal appearance as well.
XDA Profile
xda profile keycaps are also a kind of ball keycaps. The design is based on the DSA profile. While it owns higher height, but not as tall as SA profile. xda keycap offers a comfortable typing experience and clean appearance. The uniform rows for a flat profile might bring more mistyping but faster speed.
MDA Profile Keycaps
MDA Keycaps are slightly higher than cherry keycaps. Their design aims to provide a more comfortable typing experience. The contact area of MDA High-Profile Keys is larger, which may make them more comfortable to use for long periods of typing. And the shape is rounder than Cherry keycaps.
Low Profile Keycaps.
According to keycap height, there is low profile keycap. Normally it can not be switched with the keycap profiles we mention above.
Other Profiles
With the rise of the mechanical keyboard market, more and more keycap studios design
unique keycaps profiles. For example，moa keycaps，xvx keycaps，osa keycaps.
All in all, to get the best typing experience, we recommend Cherry profile. If we wanna both fast typing and nice typing feeling, OEM or Cherry keycaps is the better choice. For custom mechanical keyboard, SA keycap can bring a retro atmosphere. XDA or DSA is suitable for those who favor flat typing feeling.
What are Pudding Keycaps?
Pudding Keycap has the advantages of regular keycap and transparent keycap. It can shine through the rgb effect and shows the clear legend on the top of keycaps. The top part of pudding keycap is opaque(solid color or designed with pattern), while the bottom part is transparent or semi-transparent.
If you are a fan of rgb, and also want the clear legends on the keycaps, then the pudding keycaps can be considerate. The design of pudding keycap can enhance the aesthetic appeal of keyboard backlight.
How to get the best keycap set?
Different types of keycaps differ in speed, accuracy and comfort. Actually, the best keycap profile depends on our personal preference. And people purchase keyboard may be for different using scenario. Know why we need a new keycap set is significant.
Step1: make sure the keycap can match with keyboard switches
Step2: make sure the keycap set includes all the keys you wanna, like R1 delete, or 2.25u shift key.
Step3: take budget, material, keycap legend process,design, profile into consideration
Step4：try different profiles of keycap set.
Hope this article can help choose a suitable keycap set If there is more to be added, welcome to leave comment!