Monitor mounting is a hotly debated subject here at XDA, even though there are just two ways to do it right. You could use the space-hogging stand with limited adjustment that shipped with the display at no additional charge, or spend a few hundred on a monitor arm planning ahead for a multi-display setup. The need and efficacy of a monitor arm isn't up for debate in this article, but I'll just presume you need and want one for your setup.

Set out to buy one and listings from the product segment quickly start to resemble a battlefield littered with specifications like ‌arm length, the type, number of supported displays, clamp dimensions, materials, and supported screen size. Therein lies the challenge, at least for the technically inclined buyer. Fundamentally, a mechanical accessory has a physical limit to the weight it can hold up, and that weight isn't a direct function of the screen size, setting a dangerous precedent for how people evaluate and buy monitor arms, and it needs to change yesterday.

Picking out a monitor arm is straightforward

Well, aside from the one dangerous mistake all the listings make

A quick visit to Amazon in the quest for a monitor arm reveals the most important filtration criterion for a monitor arm. To mount the thing to your desk, you'd need a clamp that can accommodate the thickness of your tabletop and spread the weight out enough to prevent damaging the tabletop. It's also important to consider how deep the clamping point is, just in case your table has a supporting beam underneath which the mount needs to clear.

I love that, despite all the constant commotion in the display industry, brands are sticking to the VESA standard for mounting hardware even if their proprietary standards may use alternate points. It's important to confirm your monitor arm comes with a VESA plate that matches the holes behind your monitor, or you'll need an adapter sold separately. The basic plate and screws should ship with your monitor arm, though. Colors, design, and cable management options on these products are similarly standardized also. Based on your needs, you just need to pick a design between the twist-locking cantilever arms and a more versatile spring-loaded "gas spring" arm that's way easier to readjust repeatedly.

The final compatibility filter is the most important — weight capacity. Every mechanical accessory on your desk is designed with specific usage in mind, and its materials and joints are chosen to withstand just those loads. Outside a margin of error, any monitor arm will fail if you overload it, and there's no telling which component gives way first, and after how long. To avoid catastrophe with expensive displays, it is imperative that we pick a monitor arm that can take the weight.

With the gas spring design, there's an additional consideration for the minimum weight capacity if you plan to use a dual-display arm for one display and a laptop on a tray. If the laptop in question is lighter than the rated minimum weight, the spring will effortlessly lift it all the way up, making adjustment difficult or impossible. Sadly, very few Amazon sellers and other commercial retailers reveal the weight capacity in the product title or even the description.

The absurd correlation between screen size and product weight

They are related, but it's not a catch-all

Sure, filtering monitor arms by screen size is rather convenient, especially when the displays are sold by their size, and there is a correlation between the weight and size. However, it's foolhardy for buyers and manufacturers alike to presume that all displays measuring 32 inches diagonally weigh the same. There are always exceptions to the norm, and Ultrawide or curved panels are a prime example of why. Their innermost point is closest to the VESA plate, but the outer sides are laterally distant as well as protruding towards the screen viewer. Basic lever principles applied to this VESA mount mean that the points furthest away from the fulcrum or mount point apply the most bending moment on the arm. For the same reason that a door is easier to close the farther away you are from the hinge, more load applied farther away from the arm's joints could exponentially deteriorate its weight-carrying capacity, accelerating failure.

My concern isn't that monitor arm companies don't list the weight-carrying capacity at all. They seem legally bound to mention it somewhere, but clearly most of them don't acknowledge it is the primary deciding factor for a buyer. So, you'll find this important spec buried several pages down, deep in the product specifications alongside irrelevant details like the package dimensions, and that infuriates me. Importantly, these casual listings don't take liability if your display turns out to be too heavy for the arm. They have plausible deniability since they mention the spec somewhere, and it's the buyer's responsibility to look that up. But clearly, they don't make it easy.

Moreover, it takes the buyer under a minute to revisit the product specs to see how heavy their screen is. Similarly, the weight rating of the monitor arm should be front and center, preferably right there in the product title on e-commerce storefronts. Personally, the more I have to dig around for such critical information, the more said brand loses credibility in my eyes. Even if two arms say they support 32-inch displays, I would buy the one that has more headroom after accounting for the weight I plan to mount.

Listings need to change

In fact, the screen size should be listed further down the page than weight limits, or removed entirely, since it only introduces room for consumer error. Given the choice, I'd rather buy an honestly advertised and carefully listed monitor arm that's truthful about its capacity, and doesn't make me hunt for the specifications. It should be in the first five words of the product title after the brand name, before all the SEO keywords. Needless to say, not everyone selling a monitor arm on Amazon is guilty of this, but there are more examples than I'd like, currently mentioning the capacity as an afterthought. Secondly, e-commerce platforms should add a weight filter for such products to ease the user experience.