FlexiSpot Standard Ergo Office Chair (C4) vs SIHOO M18
Side by side from official specifications, sourced prices and User Insights. No written comparison exists for this pair yet.
FlexiSpot
FlexiSpot Standard Ergo Office Chair (C4)
$219.99 – $239.99
VS
SIHOO
SIHOO M18
$289.99 – $299.99
2 years
longer warranty on FlexiSpot Standard Ergo Office Chair (C4) than SIHOO M18 (official terms)
Differences at a glance
Sources
- Standard Ergonomic Office Chair | FlexiChair C4 | Flexispot ↗Checked Oct 17, 2026
- M18 Classic Ergonomischer Bürostuhl – SIHOO DE official store ↗Checked Oct 16, 2026
- Sihoo M18 Ergonomic Office Chair – Official US Sihoo Store ↗Checked Sep 29, 2026
FlexiSpot Standard Ergo Office Chair (C4)SIHOO M18
- Price
- $219.99 – $239.99$289.99 – $299.99
- Seat height
- 17.91–20.87 in44–54 cm
- Seat depth
- 19.49 in17.91 in (≈ 45.5 cm)
- Load capacity
- 300 lb330 lb (≈ 150 kg)
- Recline
- 90–135°Maximum 126° recline angle
- Arms
- 3DAdjustable armrests (Up and down)
- Headrest
- 3DHeadrest moves 3.9" up and down and pivots 45°
- Lumbar support
- fixedLumbar support adjusts vertically and horizontally
- Warranty
- 5 years3 years
Questions
Which is cheaper, the FlexiSpot Standard Ergo Office Chair (C4) or the SIHOO M18?
The FlexiSpot Standard Ergo Office Chair (C4) is cheaper to start: $219.99 versus $289.99 for the SIHOO M18 at the brand stores (Oct 2026).
Which has a higher weight capacity?
The SIHOO M18, rated for 330 lb versus 300 lb for the FlexiSpot Standard Ergo Office Chair (C4).
Which has a headrest?
Both: the FlexiSpot Standard Ergo Office Chair (C4) as standard and the SIHOO M18 as standard.
FlexiSpot Standard Ergo Office Chair (C4): specs, reviews, where to buy →SIHOO M18: specs, reviews, where to buy →
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