World LM Task Chair

Tri-panel Form Sensing Mesh borrows from tailoring: the back takes the shape of the spine pressing into it.

Niels Diffrient built the World LM from 78 parts where a conventional task chair uses more than 200, which is part of why it weighs 27 pounds and holds 400. Recline is weight-sensitive, lumbar support is automatic, and the arms travel with the backrest rather than the seat. Browse the range in our Humanscale collection.

Materials

Tri-panel Form Sensing Mesh back; all-mesh or sculpted foam seat in Corde 4, Kvadrat Autumn, or Catena Mesh

Dimensions

25.75 in. W × 25 in. D × 35.6–40.75 in. H; seat height 16.7–21.5 in.; backrest 22.5 in.; 27 lbs

Designer

Niels Diffrient

Weight capacity

400 lbs; sized for sitters from 5 ft 0 in. to 6 ft 4 in.

Certifications

BIFMA LEVEL 3, SCS Indoor Advantage Gold, CDPH, Green Tick; GREENGUARD Gold per supplier documentation

Warranty

12 years; textiles, cushions, arm pads, casters, and wood 5 years

Common Questions

Is there a lumbar adjustment?
No, and that is deliberate. The tri-paneled mesh back flexes independently across three zones to follow the curve of your spine, so support arrives without a dial to find and reset.

Who does the World LM fit?
Humanscale sizes it for sitters from 5 ft 0 in. to 6 ft 4 in. and 100 to 400 pounds, with seat height adjusting between 16.7 and 21.5 inches.

Why does the part count matter?
The World LM uses 78 parts against more than 200 in a conventional task chair. Fewer parts means fewer wear points, simpler service, and less material to recover at end of life.