SIHOO M57 vs FlexiSpot Standard Ergo Office Chair (C4)

Side by side from official specifications, sourced prices and User Insights. No written comparison exists for this pair yet.

SIHOO

SIHOO M57

$319.99

FlexiSpot

FlexiSpot Standard Ergo Office Chair (C4)

$219.99 – $239.99

2 years

longer warranty on FlexiSpot Standard Ergo Office Chair (C4) than SIHOO M57 (official terms)

Differences at a glance

SIHOO M57FlexiSpot Standard Ergo Office Chair (C4)

Price: $319.99$219.99 – $239.99
Seat height: 46–55 cm (≈ 18.1-21.7 in)17.91–20.87 in
Seat depth: 18.11 in (≈ 46 cm)19.49 in
Load capacity: 330 lb (≈ 150 kg)300 lb
Recline: Reclines up to 126°90–135°
Arms: 3D coordinated armrests (up and down, left and right, forward and backward)3D
Headrest: Headrest adjusts vertically up to 3.9 inches and rotates 45 degrees3D
Lumbar support: Dual-adjustable lumbar support (vertical and horizontal)fixed
Warranty: 3 years5 years

Which is cheaper, the SIHOO M57 or the FlexiSpot Standard Ergo Office Chair (C4)?

The FlexiSpot Standard Ergo Office Chair (C4) is cheaper to start: $219.99 versus $319.99 for the SIHOO M57 at the brand stores (Oct 2026).

Which has a higher weight capacity?

The SIHOO M57, rated for 330 lb versus 300 lb for the FlexiSpot Standard Ergo Office Chair (C4).

Which has a headrest?

Both: the SIHOO M57 as standard and the FlexiSpot Standard Ergo Office Chair (C4) as standard.