X-Chair X3 vs SIHOO M18

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

X-Chair

X-Chair X3

$979

SIHOO

SIHOO M18

$289.99 – $299.99

$689.01

lower starting price for SIHOO M18 than X-Chair X3 at the brand stores

Differences at a glance

X-Chair X3SIHOO M18

Price: $979$289.99 – $299.99
Seat height: 17.69–22 in44–54 cm
Seat depth: 16.75–19.25 in17.91 in (≈ 45.5 cm)
Load capacity: 275 lb (125 kg)330 lb (≈ 150 kg)
Recline: SciFloat Infinite Recline + Tilt Lock and Tension allows you to recline and lock into position or increase tension in your recline motion for more fluid movement.Maximum 126° recline angle
Arms: 4-Dimensional armrests come standard (up, down, side-to-side, front-to-back); option to upgrade to FS 360 rotational armrests; Armrest Height 5.875in - 8.875inAdjustable armrests (Up and down)
Headrest: Optional add-on (standard configuration: No headrest; Headrest +$115)Headrest moves 3.9" up and down and pivots 45°
Lumbar support: Dynamic Variable Lumbar (DVL)® Support; height adjustable backrest raises the DVL®Lumbar support adjusts vertically and horizontally
Warranty: 5 years (all parts and materials); 15 years (non-moving metal components, chair frame)3 years

Which is cheaper, the X-Chair X3 or the SIHOO M18?

The SIHOO M18 is cheaper to start: $289.99 versus $979 for the X-Chair X3 at the brand stores (Sep 2026).

Which has a higher weight capacity?

The SIHOO M18, rated for 330 lb versus 275 lb for the X-Chair X3.

Which has a headrest?

Both: the X-Chair X3 as an option and the SIHOO M18 as standard.

What do owners mention most?

Comfort for the X-Chair X3, and price and value for the SIHOO M18, based on review summaries.