SIHOO m18 vs m57: Same Brand, Very Different Experience

When we started comparing SIHOO M18 vs M57, it wasn’t just another spec-sheet comparison for us. We were genuinely looking for an ergonomic office chair that could survive long workdays, bad posture habits, and real-life use — not just look good on paper. So instead of relying on brand claims, we bought both chairs ourselves, unboxed them, set them up, and spent weeks — even months — sitting, adjusting, and pushing them through everyday work fatigue.

The need for choosing between the Sihoo M18 and Sihoo M57 becomes very clear once you actually live with them. On the surface, both are ergonomic office chairs designed to improve posture and reduce discomfort during long hours. But after hours of typing, meetings, leaning back, and even slouching (yes, it happens), we realised they are built for very different users.

The Sihoo M18 immediately feels like a practical entry point into ergonomic seating. It’s clearly aimed at people who want better posture support without stretching their budget too far. The foam seat cushion is comfortable at first, the adjustments cover the basics, and the mostly plastic frame keeps the price accessible. During our testing, it worked well for moderate daily use, especially if you’re upgrading from a basic office chair and want something more supportive without overthinking features.

The Sihoo M57, however, tells a different story once you spend full workdays on it. It’s designed for long-term, high-intensity use, and you feel that difference over time. The full mesh seat and back improve breathability, especially during longer sessions, and the build quality feels more solid thanks to increased metal components. Features like 3D armrests and more advanced lumbar support gave us finer control over posture, which mattered during extended sitting.

After testing both chairs side by side, we realised that choosing between SIHOO M18 vs M57 isn’t about which chair is “better” overall — it’s about what your body, budget, and work routine actually need. That’s exactly why we decided to break this comparison down from real experience, not marketing promises.

SIHOO m18 vs m57 Comparison At A Glance

Key Feature	Sihoo M18 (Budget Choice)		Sihoo M57 (Premium Ergonomic)
Seat Material	High-Density Foam Cushion: Provides a traditional, soft “cushiony” feel immediately upon sitting.		Full Breathable Mesh: Offers maximum air circulation for cooling during long sessions.
Armrest Adjustability	2D Adjustability: Typically restricted to height and sometimes front/back; lacks lateral angle adjustment.		3D Adjustability: Highly customisable with adjustments for height, depth (front/back), and angle (swivel).
Lumbar Support	2-Way Adjustable: Basic vertical (up/down) and depth adjustment via a knob to fit the spine’s curve.		Advanced 2-Way Support: More precise height and depth control, often built with more robust materials for consistent support.
Headrest	2D Adjustability: Height-adjustable with a basic tilt to support the neck.		3D Adjustability: Greater range of motion, including height, depth, and angle for tailored neck relief.
Build Quality	Plastic-Heavy: Uses more plastic in the frame and armrests to keep costs low.		Metal-Reinforced: Features more metal parts, especially in the base and armrest structure, for increased durability.
Primary Weakness	Breathability & Precision: Foam seat can trap heat; limited armrest angles may cause shoulder strain over time.		Initial Comfort Feel: Some users find the mesh seat too firm or experience a “sliding” sensation compared to foam.
Best Suited For	Budget-conscious buyers or those who prefer a soft, traditional seat cushion.		High-intensity users needing maximum cooling and precise ergonomic customisation.
Cost Of Chair	Current Price (Must Buy)		Current Price

SIHOO m18 vs m57: Tried And Tested Models

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Best Use Case (Personal Experience)

Based on our long-term testing of the SIHOO M18 vs M57, each chair fits a different type of user. The Sihoo M18 worked best for us when used for moderate hours. It’s a good choice if you’re on a tight budget and prefer a softer foam seat without needing advanced adjustments. The Sihoo M57 felt more suitable for long workdays. Its stronger build, better ergonomics, and breathable mesh made it more comfortable for extended sitting. For full-day desk work, the M57 clearly handled daily demands better.

Seat Material

When we tested the SIHOO M18 vs M57, the seat material difference was noticeable right away. The Sihoo M18 uses a high-density foam seat that feels softer and more comfortable at first sit. We liked the cushioned feel, especially during shorter work sessions, but after long hours, it started retaining heat and felt less breathable. The Sihoo M57, on the other hand, comes with a full mesh seat. It feels firmer than foam but keeps us cooler during extended use. For long sitting hours, the mesh seat of the M57 felt more practical.

Armrest Adjustability

While comparing the SIHOO M18 vs M57, the difference in armrest adjustability was clear during daily use. The Sihoo M18 comes with basic 2D armrests that allow height adjustment and limited forward or backward movement. They worked fine for simple desk setups but felt restrictive when we tried to fine-tune our posture. The Sihoo M57 offers advanced 3D armrests with height, depth, and angle adjustments. This allowed us to align our arms properly while typing, which helped reduce shoulder and wrist strain during long work hours.

Lumbar Support System

During our hands-on testing of the SIHOO M18 vs M57, the lumbar support difference became clear over long sitting hours. The Sihoo M18 features a basic adjustable lumbar support that moves up and down. It helped support our lower back but felt limited in fine-tuning. The Sihoo M57, however, provides a more advanced lumbar support system with better integration into the backrest. We could adjust both the position and firmness, which made maintaining proper posture easier. For extended daily use, the M57’s lumbar support felt more consistent and supportive.

Headrest Adjustability

While testing the SIHOO M18 vs M57, the headrest adjustability made a noticeable difference in neck support. The Sihoo M18 comes with a basic 2D adjustable headrest that allows height adjustment. It supported our neck during upright sitting but felt limited when reclining. The Sihoo M57 offers a more advanced 3D adjustable headrest with height and angle adjustments, and sometimes depth control. This allowed us to position our head more naturally in different postures. For long work sessions and occasional leaning back, the M57 headrest felt more supportive.

Build Material and Durability

After weeks of use, the difference in build quality between the SIHOO M18 vs M57 was easy to notice. The Sihoo M18 relies more on plastic, especially around the base and armrests. It feels lightweight and stable enough for normal use, but not heavy-duty. The Sihoo M57 uses more metal in key structural areas, which gives it a sturdier and more solid feel. The chair felt more stable during long hours and frequent adjustments. For daily, long-term use, the M57 clearly felt more durable.

How We Test

To fairly compare the SIHOO M18 vs M57, we followed a hands-on testing process based on real daily use, not just specifications. We bought both chairs, unboxed them ourselves, and assembled them without professional help to judge build quality and ease of setup. Each chair was then used for several weeks to months in the same workspace.

We tested them during long workdays, short sessions, and relaxed leaning-back periods. Our focus was on seat comfort, armrest adjustability, lumbar support, headrest positioning, breathability, and overall durability. We also paid attention to how our body felt after 6–8+ hours of sitting, including back fatigue, shoulder strain, and heat buildup.

Adjustments were fine-tuned repeatedly to see how flexible each chair really is. By switching between the Sihoo M18 and Sihoo M57 daily, we could clearly feel where each model performs better. Our conclusions are based purely on real use, posture impact, and long-term comfort—not marketing claims.