Tools
Will that chair actually fit you?
Most chair regret is a fit problem, not a quality problem. These are the four numbers to check against the spec sheet before it ships.
| Measurement | Range | Why |
|---|---|---|
| Seat depth | 16–17.5 in | Front edge to backrest. You want two fingers of gap behind your knee — this is the measurement nobody checks and the reason a chair that felt fine in the shop cuts off circulation by three o’clock. |
| Seat height | 17.5–19 in | Floor to the top of the pan. Feet flat, thighs roughly level. |
| Lumbar support, above the seat | 7–8.5 in | The fullest part of the backrest curve should meet the inward curve of your lower back, not your ribs. |
| Armrest, above the seat | 9–10.5 in | Shoulders down, elbows bent about ninety degrees, forearms resting without lifting. |
Check it against a spec sheet
Chair listings publish a seat height range. Put it in and we will say whether it reaches 17.5–19 in.
Why seat depth comes first
Height is the adjustment everyone makes and depth is the one most chairs do not offer below the mid range. If the pan is too long it presses behind your knee, and you compensate by perching forward — at which point the backrest you paid for is doing nothing at all.
Fit beats price
A mid-range chair that fits will hold you better than an expensive one that does not. The expensive chairs earn their reputation partly by offering more adjustment, which is another way of saying they fit more people — not that they fit you specifically.
What to do if you are between sizes
Several contract chairs come in more than one frame size, and the size chart is usually buried in a PDF rather than shown on the listing. If you are near the edge of a range, that chart is worth finding. Where a chair is genuinely worth repairing rather than replacing is covered in fix or replace your office chair.