SIHOO M18 Review: Worth It? (November 2026)
The SIHOO M18 suits desk users who want an adjustable mesh chair with a headrest and lumbar support. Check your height, desk clearance and preferred seat position before choosing it.
On this page (8 sections)
The SIHOO M18 is an adjustable mesh office chair for people 5 ft 6 in to 6 ft 2 in tall, according to SIHOO. It includes an adjustable headrest, lumbar support, seat height and back support, so it may suit you if you want several fit controls in one chair.
The main checks are whether the stated height range fits you and whether the chair's seat and arms work with your desk. The seat dimensions and seat depth aren't specified here, so measure your space and compare the chair in person if those details are important to your fit.
What does the SIHOO M18 offer?
The M18 combines a mesh back with adjustments for seat height, headrest, lumbar support and back support. SIHOO also describes it as suitable for home and work use.
SIHOO M18 Ergonomic Office Chair: Best for adjustable everyday seating
- Mesh back
- Adjustable headrest
- Adjustable lumbar support
- 2D armrests
- Tilt
A mesh chair with an adjustable headrest, lumbar support, seat height and back support. SIHOO says it suits people 5 ft 6 in to 6 ft 2 in tall.
Pros
- Several listed fit and support adjustments
- Breathable mesh back
- 2D armrests
- SIHOO states a 3-year warranty with replacement parts
Cons
- The stated height range may not fit shorter or taller users
- Seat dimensions and seat depth are not specified here
SIHOO says the chair is designed with four support points: head, back, hips and hands. That describes the intended support areas, while your comfort will depend on how the chair's positions line up with your body.
Is the SIHOO M18 a good fit for your height?
The M18 is a candidate if you are within SIHOO's stated 5 ft 6 in to 6 ft 2 in range. Height alone does not settle chair fit, so also check seat height, your leg position and where the lumbar support meets your back.
A useful fit check is to sit with your feet supported and your shoulders relaxed. See whether the seat height allows that position, whether the lumbar support lands comfortably and whether the headrest meets your head without pushing it forward.
The armrests matter at your desk, too. Check that they let your shoulders stay relaxed and that they can clear the desk when you pull the chair close.
How adjustable is the M18?
The M18 offers seat height, headrest, lumbar support and back support adjustments. Those controls let you change several points of contact, though the details do not specify adjustment ranges or locking positions.
Set the seat height first so your feet rest comfortably and your knees aren't forced upward by the desk. Then adjust the lumbar support and headrest to match your seated posture.
Try the back support and tilt controls as part of the same fit check. A chair can have several adjustments and still feel wrong if the seat shape, arm position or overall proportions don't suit you.
The M18's features make it worth comparing with other models in our guide to the best Sihoo ergonomic office chair. Use that overview if you want to weigh the M18 against options with different adjustment setups.
What should you know about the mesh back?
The M18 has a mesh back, which SIHOO describes as breathable. That may appeal if you prefer an open back surface, but the description doesn't tell you how cool or supportive it will feel in your room.
The product details identify the back as mesh and the fill material as sponge. They don't specify the seat upholstery, so confirm that material if you have a strong preference for mesh or fabric under you.
Mesh feel can vary by tension and construction. If you're sensitive to firm or textured back support, consider trying the chair or checking return terms before you commit.
Will the M18 fit your desk and room?
Check the chair's 27.5 x 21 x 11 in listed item dimensions against your available space, then confirm which dimension refers to each part before relying on them for a fit decision. The separate depth measurement is 21 in, but a full seat width and seat depth aren't stated here.
Allow room to roll back and recline, and check that the armrests can slide under your desk if that matters to you. Measure the desk opening between its legs or supports rather than assuming the chair will clear it.
The chair is listed at 14.3 kg. Plan the route from delivery point to desk, especially if you need to carry it up stairs or through a narrow doorway.
How does the M18 compare with the M57?
Choose between the M18 and M57 by comparing the fit controls and dimensions that matter to your body and desk. They are separate SIHOO models, so don't assume the M57 has the same adjustment range or fit as the M18.
Our SIHOO M18 vs M57 comparison helps you weigh the two models side by side. Before deciding, focus on the seat measurements, headrest position, lumbar adjustment and armrest clearance that affect your daily setup.
Should you consider a Doro C300 instead?
Compare the Doro C300 models if you want to consider other SIHOO chair designs alongside the M18. The right choice depends on the adjustment and fit details that suit you, so compare each model's specifications before deciding.
Read our SIHOO Doro C300 review for a closer look at that alternative. If you are considering the upgraded model, see the SIHOO Doro C300 Pro review as well.
Assembly, capacity and warranty details
SIHOO says the M18 comes with simple assembly instructions covering eight steps. The chair is listed with a capacity of up to 150 kg, and SIHOO says it passed BIFMA and a 1,136 kg static pressure test.
Those are manufacturer statements about the chair and its testing. Follow the included instructions during assembly, tighten parts as directed and check that the chair is stable before sitting.
SIHOO states that it offers free replacement parts during a 3-year warranty period, along with free returns and refunds within 30 days for faults or other quality-related issues. Read the current terms and contact SIHOO to confirm how coverage and returns apply where you live.
Is the SIHOO M18 right for you?
The M18 is worth considering if you fall within SIHOO's stated height range and want a mesh back, adjustable headrest and lumbar support. Confirm the seat and arm fit at your desk, since the seat width and depth are not specified here.
Choose the M18 if its adjustments and dimensions match your setup. If you want to compare the other models first, start with the SIHOO M18 vs M57 comparison.
Frequently asked questions
Who is the SIHOO M18 designed to fit?
SIHOO says the M18 suits people from 5 ft 6 in to 6 ft 2 in tall. Treat that range as a starting point, then check whether the seat height, lumbar position, headrest and armrests can align with your body and desk.
If you fall outside the stated range, compare other chairs before buying.
Does the SIHOO M18 have adjustable lumbar support?
Yes, the M18 has adjustable lumbar support, along with adjustable seat height, headrest and back support. These controls let you change several contact points, but they cannot guarantee a comfortable fit for every body.
Check where the lumbar support sits when you are seated in your usual working posture.
Is the SIHOO M18 back made of mesh?
Yes, the M18 has a mesh back. SIHOO describes it as breathable mesh intended to help keep your back cool, but comfort depends on your room, clothing and personal preference.
The details do not specify a mesh seat, so check the seat material and feel before choosing it.
How much weight can the SIHOO M18 support?
The M18 is listed with a weight capacity of up to 150 kg. Check that limit against your needs and review the chair's full assembly and use instructions.
Capacity alone does not tell you whether the seat width, depth or arm spacing will feel comfortable.
