The depth you need is one leg, not the diagonal

A corner desk looks deep. Stand in front of the corner and there is a lot of surface between you and the wall, and that is the measurement people take. It is the wrong one. A converter is a rectangle with a flat base, so it has to sit square against one wall or the other, and the space it lives in is a rectangle inside one leg of the desk. The deep part at the diagonal is where nothing rectangular goes.

So the number to write down is the distance from the front edge of one leg back to the wall. On a lot of L-shaped and corner desks that is 22 to 24 in, which is exactly where the specifications start to bite.

Ergotron is the only maker that grades its converters for corners

Ergotron’s own comparison chart carries a row called Fits Corner Workspace, and it answers the question for six models rather than leaving you to guess.

The WorkFit-T is not in that table. It is still on Ergotron’s August 2025 product sheet and its product page still resolves, but the company has stopped grading it alongside the others, and it publishes no corner rating for it either way.

Ergotron also builds one converter for this specific problem. The WorkFit Corner, part 33-468-921, is described by the company as “designed for corner desk applications” with “more worksurface and the largest keyboard platform of any WorkFit converter”.

The smaller WorkFit-TS is pitched at converting “corner worksurfaces or other tight spaces into standing desks”. If you have been searching that part number and landing on pages that do not mention it, that is the product.

Nobody else publishes anything comparable. Fellowes and RightAngle both give you minimum desk dimensions and leave the corner question alone.

Depth, lift and capacity, side by side

The WorkFit-TX is the deepest worksurface here at 27 in, and it is the only one of the six with no stated minimum desk depth, which leaves the buyer who most needs that number without it. The Fellowes capacity figures are split as well. The keyboard platform is rated for 5 lb on its own, so a heavy mechanical keyboard and a mousepad eat most of that before you have put anything on it.

Which way the platform travels

A converter that rises straight up stays inside its own footprint. Swing the platform forward as it lifts and it takes desk edge and floor space with it, and in a corner, where you may be boxed in on two sides by walls and on a third by the other leg of the desk, that difference is not academic.

Ergotron says it plainly for the T and the TL. The system “lifts straight up and down to minimise intrusion into the workspace” and the platforms “move straight up and down, always staying within the footprint”. For the WorkFit-TX, which uses a different X-shaped lift, Ergotron says only that it gives 17 in of vertical height adjustment. It never says straight, and it never applies the Constant Force name to that model.

Fellowes says nothing at all about the travel path of the Lotus or the Lotus DX. The same company publishes a Minimum Reach of 24.02 in and a Maximum Reach of 35.64 in for the clamp-mounted Lotus RT, a plain admission that the platform moves horizontally.

The two free-standing models get a fixed base footprint and no reach figure, and you are left to work out the rest by standing one up in a shop.

The warranties are softer than the marketing

Every one of these is sold on a five-year warranty. The documents themselves are less tidy.

Ergotron’s product sheet gives the WorkFit-T and TL five years. Its current warranty document, dated March 2026, lists the WorkFit-Z Mini at two years, the WorkFit Elevate at ten, and the WorkFit-C and TeachWell desks at five. The T, the TL and the TX are not named in it.

Fellowes contradicts itself on the Lotus inside its own paperwork. The FAQ sheet answers the warranty question with three years. The product manual says five. On the Lotus DX the manual splits the term, giving one year on the USB and wireless charging components and five on everything else, which is the honest way to write it. The plain Lotus contradiction looks like an oversight next to that.

Fellowes’ contract warranty, the document that governs its dealer-channel furniture, does not name sit-stand workstations or desktop converters as a covered category at all. The one thing in that family it does name is the Lotus-DX Power Module, at ten years. RightAngle gives a flat five years on the Hover Helium with no exclusions published.

What to do with all that

Measure one leg of your desk from the front edge to the wall. If the answer is 24 in or more you can shop the whole category. Under that, the only honest answer is that no manufacturer here has published a figure that covers you, and three inches of platform sticking past the desk edge is three inches your chair arm will find.

Then weigh what you are putting on it. Two 24 in monitors and a laptop will get you close to 40 lb, and these units have a minimum load as well as a maximum, so an almost-empty platform springs up at you.

The one converter checked in full here is the ESI S2S, which is discontinued. The full list of what has been checked shows where each one stands, and the work nook guide covers the desk measurements themselves.

Questions people ask

Read how I check numbers.