Guide · Updated 2026-10-08

How to Choose a Monitor Arm That Fits

Check VESA pattern, weight range, screen size and desk clamp before buying a monitor arm, with a worked example and the common mistakes that cause returns.

Where to buy

Monitor arms VESA adapter plates

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A monitor arm frees desk space and lets you set the screen at the right height, but it only works if five numbers line up: the monitor's weight, its VESA hole pattern, its size, the arm's weight range and your desk's thickness. Check all five before buying and you avoid most returns.

1. VESA pattern

Most monitors have four screw holes on the back in a standard square or rectangle measured in millimetres. The common patterns are 75 x 75 and 100 x 100, with some larger monitors using 200 x 100 or 200 x 200. The arm's head must support the same pattern. If your monitor has no VESA holes, you may be able to buy a VESA adapter plate made for your model, but check it carefully.

2. Weight range, including a minimum

Gas-spring arms are tuned for a weight range, for example 2 to 9 kg. Many people check only the maximum. If the monitor is lighter than the minimum, the arm springs upward and will not stay where you put it. Weigh the monitor without its stand and add anything attached, such as a webcam or light bar.

3. Screen size

Arms list a maximum screen size, often 32 inches for a standard arm. Ultrawide and curved monitors may need arms designed for them because the weight is spread further from the arm.

4. Desk thickness and type

Clamp mounts have a thickness range, commonly about 1 to 8.5 cm. A desk outside that range needs a grommet mount or a different arm. Glass desks, hollow desks and thin metal-frame desks can be damaged by a clamp: use a reinforcement plate or a stand-alone mount.

A worked example

Check	Monitor and desk	Arm	Result
Weight	4.8 kg + 0.3 kg webcam = 5.1 kg	2 to 9 kg	Pass
Screen size	27 inches	up to 32 inches	Pass
VESA	100 x 100 mm	75 and 100 mm	Pass
Desk thickness	3 cm	clamp 1 to 8.5 cm	Pass
Desk type	Solid wood	n/a	Pass

If the same monitor weighed 1.5 kg it would fail the minimum weight, and a 12 cm thick workbench would fail the clamp range. The Monitor Arm Compatibility Checker runs all five checks for your own numbers.

Set up tips

Position the top of the screen at or just below eye level, about an arm's length away.
Leave a loop of cable at the joints so the arm can move freely.
Tighten the clamp evenly and check it again after a week.

Building a home office around it

If you are kitting out a whole workspace, the Home Office Kit Budget Planner splits a budget between monitor, chair, desk and extras, and the Will It Fit? checker helps with desk and space measurements.

Frequently asked questions

Can I use an arm with a curved ultrawide? Yes if the arm's weight range and screen size limit cover it. Check the arm lists support for ultrawide.

Do I need two arms for two monitors? You can use a dual arm on one clamp, but add the weights of both monitors and check each against the per-screen limit.

Always use the figures printed on the product page or in the manual. This guide uses example numbers.