Here are some important features and ergonomics criteria:
Adjustability
Seat height: So your feet are flat on the floor, and knees are about 90°. ehs.ucmerced.edu+2petersenpt.com+2
Seat depth: Good ergonomic chairs let you adjust how deep the seat is so your thighs are fully supported but the edge isn’t pressing behind your knees. essr.umd.edu+1
Armrests: Adjustable ones (height, width) are very useful. EU Sihoo official Shop
Backrest tilt / recline: Helps you change posture during the day. My Cubicles
Lumbar Support
Very important to support the lower back. Adjustable lumbar support (height or depth) is ideal. petersenpt.com
It should follow the natural curve of your spine. BOSQ
Base & Mobility
A 5-point base (5 wheels) gives good stability. essr.umd.edu+1
Casters (wheels) according to your floor type: hard vs carpet. uoguelph.ca
360° swivel helps you reach different parts of your desk without twisting. officegearstudio.com
Material
Build + Durability
Ergonomics Use