What is Seat depth & waterfall edge?
Distance from back to front edge, and whether the edge curves down.
Short answer
Tall and short users need seat-slide adjustment; most cheap chairs have none.
Seat depth & waterfall edge when buying a office & study chair
Distance from back to front edge, and whether the edge curves down.
Why it matters: Two-three fingers should fit between the seat edge and your knee, else circulation suffers.
Look for: Tall and short users need seat-slide adjustment; most cheap chairs have none.
Full Office & Study Chair buying guide