Office chairs photograph identically at every price, and a handful of specifications separate one that lasts a decade from one that sags in a year.

The Specifications That Matter

• Seat height range, in real numbers
• Seat width and depth, separately
• Backrest height, which decides whether it reaches your shoulders
• Which adjustments exist: height, depth, lumbar, arms, tilt tension
• Weight capacity, and whether a testing standard is named
• Base material: steel or nylon
• Caster type, for your floor
• Upholstery material, named rather than described
• Assembled weight, as a crude proxy for construction

Listings that state lumbar type, weight rating and seat width per model, of the kind at stellamia.org, can be checked against your body and your desk. Ones offering adjectives cannot.

Silence Is Information

An omitted specification is usually omitted because stating it would not help.

No adjustment list means fixed. No weight rating means low. No standard named means untested. Upholstery described as leather-look means a coating.

Check the Review Counts Against Each Other

Worth noticing on any site. Where several different products show identical review counts, those figures are aggregated across a range rather than being per product.

That is common and it means a headline number is not telling you about the specific item you are buying. Read the text of reviews rather than the count.

Reviews, Read for Time

Most are written in the first fortnight, when every chair is comfortable and every cylinder holds.

The useful ones mention six months or a year: whether the foam flattened, whether the cylinder sank, whether the lumbar pump held air, whether armrest padding wore through.

Recurring specific complaints matter far more than an average score.

Weight as a Proxy

Where nothing useful is stated, shipping weight is crude and reliable.

Two nominally identical chairs with a substantial weight difference are not built the same way. Steel bases, denser foam and heavier mechanisms all weigh.

Measure Your Desk First

Desk height, knee clearance underneath, and whether armrests will clear the desk edge.

Check the Return Terms

Fit is personal and not predictable, which makes a return window worth more than a specification.

Assembly Is Usually Simple

Twenty to forty minutes, and the cylinder pushes in rather than screwing.

Adjust It on Day One

An unadjusted good chair performs like a bad one.