Product Review · Ergonomic Office Chairs · #9 Ranked
Sihoo M18
Ergonomic office chairs — budget mesh high-back with headrest · Reviewed by Katie · amazon.com live, Sept 28 2026
Why it scored a 74
At $169.99 the Sihoo M18 is Amazon's perennial best-selling budget ergonomic chair, a mesh high-back with a headrest and a real up-and-down, in-and-out lumbar. Value leads at 86 and Satisfaction sits at 84, but Features drags at 55 and Quality at 58: the seat depth is fixed, the armrests only move up and down, and owners report the foam flattening and the chair running small for anyone over six feet or ten-hour days. That combination lands it at 74, just under our buy line. It is for a shorter, lighter user on a tight budget who wants a headrest and adjustable lumbar and will not sit all day.
What you're getting
- 330 lb weight rating, BIFMA certified; chair weighs 37.1 lb
- Adjustable lumbar moves both vertically and horizontally
- Headrest: 3.9 in vertical travel and 45° pivot
- Recline up to 126° with tilt lock and tension control
- Seat height 18-22 in gas lift; seat width 20.1 in, depth 17.9 in (fixed)
- Polyester mesh back with W-shaped foam cushion; PU silent casters
- Overall 28 in W x 27 in D x 44-51 in H
- 2D height-only armrests; 3-year warranty (some listings cite 2 years)
ViperScore breakdown
At a glance
- 330 lb rating, BIFMA certified; 37.1 lb chair
- Recline to 126° with tilt lock; seat 18"–22"
- Adjustable lumbar; 2D arms; 3-year warranty
- Price$169.99
- TierErgonomic office chairs — budget mesh high-back with headrest
- Category rank#9 of 10
Should you buy the Sihoo M18?
The Sihoo M18 is Amazon's best-selling budget ergonomic chair, and at $169.99 it is the cheapest chair in our ergonomic office chair ranking, where it sits at #9 of 10. It suits someone who needs a mesh high-back with a headrest and adjustable lumbar for as little money as possible, accepts a fixed seat depth, and will not be sitting eight hours a day. If you can stretch to $299.48, the Sihoo Doro C300 is a noticeably better chair from the same company.
Where it earns its score
- Best Value score in the category. An 86, thanks to a BIFMA-certified 330 lb rating and adjustable lumbar and headrest at this price.
- Lumbar moves two ways. Vertical and horizontal adjustment, which most sub-$200 chairs skip.
- Real recline. Up to 126 degrees with a tilt lock and tension control.
- Light. About 37 lb, easy to move around an apartment.
What to know first
- Below our buy line. A 74 misses the 75 threshold because Quality is 58 and Features is 55; the Sihoo Doro C300 is what to buy instead.
- Fixed seat depth. 17.9 in with no slider, so it fits a narrow range of leg lengths.
- 2D arms. Height only, no width, depth or pivot.
- 3-year warranty. Warranty scores 78, mid-pack for the price.
Our verdict
The Sihoo M18 scores 74, Buy With Caution by a single point. It is a fine chair for a spare room or a student desk, but if you sit all day, spend the extra $130 on the Sihoo Doro C300 at 79, which adds full mesh, a dynamic lumbar and 3D arms.
Sihoo Doro C300
Questions buyers ask
Is the Sihoo M18 good for long hours?
It is acceptable for part-time use, but its Features score of 55 and fixed seat depth make it a poor fit for all-day sitting. The Sihoo Doro C300 is the better all-day choice.
What is the weight capacity of the Sihoo M18?
330 lb, BIFMA certified. The chair itself weighs 37.1 lb.
Does the Sihoo M18 headrest adjust?
Yes. It has 3.9 in of vertical travel and pivots 45 degrees.
Ready to check it out?
Sihoo M18 · ViperScore 74 · Buy With Caution · $169.99
How the other 9 ergonomic office chairs scored
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