I spent two years working from a dining chair with a pillow behind me and telling myself the back pain was from stress. It was not stress. It was the chair, and fixing it cost less than a month of the chiropractor visits I was making.

This is not a sponsored review. Nobody sent me anything. Here is what changed and what I would tell someone shopping now.

What was actually wrong

The dining chair had no lumbar curve, a hard flat seat, and arms that stopped my elbows from reaching ninety degrees. So I compensated by slouching forward, and my upper back took the load of holding my head up for eight hours a day.

A good office chair does three things: it holds your lower back in a curve, it lets your feet sit flat with your thighs level, and it lets your elbows rest at ninety degrees without your shoulders rising.

What matters when shopping

1. Adjustable lumbar support that moves up and down, not just in and out. The curve of your back needs to hit the chair in a specific spot, and that spot is different for a five foot four person and a six foot person.
2. Seat depth adjustment. This is the feature budget chairs skip and it matters more than most of the ones they include. If the seat edge presses behind your knees, your circulation suffers all day.
3. A breathable mesh back. Foam backs get hot and when you get hot you shift, and shifting is what starts the ache.
4. Armrests that adjust in height, and ideally that drop low enough to slide under the desk.
5. A seat cushion that does not bottom out. Sit in it for twenty minutes if you can. A cushion that compresses flat in ten minutes will be a plank by month six.

What you do not need: a headrest, a footrest built in, or a name brand. None of those three changed my comfort. What changed it was lumbar height adjustment and seat depth.

What I ended up with

A mesh back task chair in the low two hundreds with independent lumbar height adjustment and a sliding seat pan. Nothing else about it is special. The wheels are average, the plastic feels like plastic, and the headrest would be a joke if it had one.

My back stopped hurting within two weeks. Not gradually. Within two weeks of the swap, the four o’clock ache between my shoulder blades was gone, and it has not come back in eight months.

What I would tell a friend

• Sit test matters more than specs. Buy from somewhere with free returns and send it back if twenty minutes feels wrong.
• Do not buy used unless you can test it. A used high end chair with a collapsed cushion is worse than a new cheap one.
• Set it up properly, because a good chair adjusted wrong is a bad chair. Feet flat, knees at ninety, lumbar in your curve, elbows at ninety.
• The chair is not a substitute for standing up. I still get up every hour, and the combination is what worked.

If you are sitting on a dining chair right now and reading this with a sore back, that is the whole review. Spend the money.