If you’ve found this post then you’ve reached the stage of “what keycaps do I get” of the mechanical keyboard hobby.
In the earlier days of mechanical keyboards, the prevailing wisdom was that PBT was higher quality and more desirable than ABS from any lens. Unfortunately, it’s not longer that simple.
GMK mania swept the internets and now the decision on ABS vs. PBT is a lot more nuanced. Which one should you choose? You’re not a plastics engineer how are you supposed to know which dang polymer to pick?
The goal of this post is to help you narrow down your options.
ABS (Acrylonitrile butadiene styrene) plastic is a emulsion, where different materials that don’t normally mixed are stabilized together as a result of heat, friction and mixing. ABS plastic is a thermoplastic, it can be melted down and remolded easily, making it a highly recyclable plastic. ABS’ stable nature and ease of melting and molding make it a popular material choice.
LEGO bricks are ABS plastic, as are power tool housings.
ABS keycaps are the standard which everyone is familiar with, if you had a pre-built computer growing up, it almost certainly had an ABS keyboard. This early impression of ABS keycaps are what gave it its initial reputation. Cheap, will fade, and generally undesirable.
ABS as a material is more sensitive to heat and can be manufactured easily with molding. The keycaps that came out during the early days of computers were thin and cheaply made. The keycaps were and are still fine, they’re durable and can withstand a lot of typing while not costing a lot of money.
PBT (Polybutylene terephthalate) plastic is also a thermoplastic polymer that has a semi-crystalline structure. PBT is more heat resistant than ABS, and general more resistant to wear. PBT can be mixed with other materials to create unique properties, either in feel or strength.
PBT is often used when a product requires chemical or heat resistance or higher levels of stiffness and resistance to impact and weight. You will find PBT in a lot of places where sources of heat and friction are nearby, engine and motor covers, and electronics interiors are common uses for PBT.
PBT keycaps are sturdier and thicker than ABS keycaps. The PBT manufacturing process requires thicker walls and the plastic is inherently more heat and friction proof. PBT keycaps have a defined texture, with a main benefit of being resistant to fading and shining.
ABS vs PBT keycaps
There are a couple of 4 core truths when comparing PBT and ABS. Outside of these truths, other things such as cost and thickness of keycaps are dependent on manufacturer.
ABS will get shiny and slick, PBT will not
ABS keycaps will wear with use, causing the surface of the cap to become shinier and slipperier. This shining will cause your keycaps to look inconsistent on the higher use caps.
PBT keycaps keep their texture and look for a much longer period of time.
How long before ABS shines?
This depends on how often you’re using the computer, and how vigorously you type. People have reported shine within 6 months with it steadily getting shinier.
ABS produces a softer sound, PBT produces a crisper sound
ABS is a softer plastic and produces a milder, softer sound. PBT is harder and produces a more tactile sound. Neither is better, it’s up to preference, but there are a lot of fans of the sound a premium ABS keycap like GMK produces.
ABS will have more vibrant colour options
ABS keycaps are generally more vibrant with way more design options from multiple manufacturers. ABS is easier to mix colours into.
PBT has a few colour options but they’re usually not vivid bright colours that you can find on ABS caps.
PBT is more prone to warping and bending on larger keycap sizes
PBT keycaps have issues with warping when cooling off in the manufacturing process, this is most pronounced in long keys, especially 7u spacebars.
ABS vs PBT: What’s Better?
It’s completely up to personal preference. Some people really value the colours and aesthetic choices that ABS provides and don’t mind that keys get shinier over time.
4 types of keycaps
Cheap ABS keycaps
These are the keycaps that everyone is familiar with, they’re the default keycaps of pack-in keyboards. Cheap ABS keycaps are the thinnest caps you’ll find. Thinner plastic will produce a thinner sounding typing sound, a little more hollow.
Cheap ABS keycaps often come with printed legends, meaning along with these caps getting shiny over time, the legends will also rub off.
Budget PBT is slightly more expensive than ABS. Budget PBT is largely the same feel as premium PBT. It’s a similar thickness due PBT manufacturing requirements. The material between budget PBT and premium PBT is also largely the same, you can expect the same sound and texture properties from Budget PBT.
Where budget PBT cuts corners is on design, not a lot of detail will go into colour vibrancy or accuracy.
You can find pad-printed, dye sublimated and double shot keycaps in this PBT price range.
Budget PBT is likely to skimp on QA. PBT has a tendency to warp as it cools, resulting in bent keycaps, space bars can be noticeably warped. Luckily, you can un-warp a keycap by heating it up with a blow dryer and setting the cap against a straight edge.
Good places to find budget PBT: Tao Bao, AliExpress, Amazon, Mechanicalkeyboards.com
Premium PBT is similar to budget PBT but they pay more attention to quality assurance, colour and design.
You’ll be able to find more unique designs and colours with premium PBT sets. Premium PBT keycap makers also make caps in multiple profiles, notably Cherry and SA profiles.
Premium PBT will come with dye sub or double shot legends with more unique flourishes and accents.
Higher quality standards will also result in fewer warped spacebars and caps in general with premium PBT sets.
Good PBT keycap manufacturers to note: enjoyPBT, Hammerworks, Signature Plastics, Infinikey
Premium ABS uses the same base ABS plastic as the budget stuff. Premium ABS is known to have a ton of design choices, limited runs by GMK have produced several iconic keycap sets.
Premium ABS is thicker than the cheaper ABS keycaps, resulting in a fuller, more satisfying typing sound.
Premium key caps are still prone to shine and discolouration over a long term, the legends are usually double shot so you won’t find those fading.
Good ABS brands to note: GMK
I care most about acoustics
Get premium ABS keycaps from GMK. Thick ABS keycaps produce a softer, quieter sound that a lot of people find pleasing.
I don’t know if I care about shiny plastic
At some point in your life you must’ve come across ABS shining, think back to your first laptop or a school keyboard, remember that shiny spot on the spacebar, that’s what ABS shine looks like.
What’s the best keycap?
There isn’t one. Keycaps are entirely up to preference, if you haven’t tried other keycap materials or profiles, I’d suggest trying a cheaper keycap set and see if you like it, I found that way that I love the cherry profile but don’t really care for XDA.
What are pudding keycaps?
Putting keycaps have a transculent side housing with an opaque top, making for a neat lighting effect.
What are double shot keycaps?
Double shot keycaps have a legend that is made up of another layer of plastic, meaning the legend is actually cut out from the main keycap housing and filled in with another plastic. Double shot keycaps ensure that the legends will never fade or rub off, and it gives a ton of colour options for keycaps.
What are keycap profiles?
Keycaps can have different shapes to accommodate for different typing preferences. Some keycaps are completely in profile, some have a slope or a curve. Different keycap profiles also have different heights. Check out our post on keycap profiles.