SIHOO M57 vs SIHOO M18: Which Should You Buy?

Key difference: The M57 has 3D armrests where the M18 has height-only arms, but the M18 lists $30 lower.

What follows compares the M57 and M18 on SIHOO's own specifications and regular US list prices, not on a Chairpedia test.

Why compare them

Why put the SIHOO M57 next to the SIHOO M18? The M57 and M18 are two of SIHOO's lower-priced mesh chairs, and first-time buyers of an adjustable office chair often end up choosing between them. SIHOO gives both the same recline, warranty and load rating, so the choice turns on the armrests, the price and the weight.

Specs side by side

Strengths and weaknesses

SIHOO M57

Strengths

• 3D armrests, against height-only armrests on the M18.

Weaknesses

• Costs more: from $319.99 against $289.99 for the M18.

SIHOO M18

Strengths

• Lower list price: from $289.99 against $319.99 for the M57.

Weaknesses

• Height-only armrests, against 3D on the M57.

How they differ

Armrests. The SIHOO M57 lists “3D coordinated armrests (up and down, left and right, forward and backward)”, the SIHOO M18 “Adjustable armrests (Up and down)”. With 3D armrests the M57 lets you set the pads in more ways than the M18. The M18's pads only move up and down.

Price. At regular US list prices the SIHOO M57 is $319.99 and the SIHOO M18 is $289.99–$299.99. The M18 lists $30 below the M57, before any store sale. Price options: the M57 — Black, Gray and White $319.99; the M18 — Black (incl. Skate Wheels) $289.99; White/Blue/Green/Pink $299.99.

Seat size. Seat height: the SIHOO M57 lists “≈18.1–21.7 in (46–55 cm)”, the SIHOO M18 nothing. Seat width: the SIHOO M57 lists “≈20.1 in (51 cm)”, the SIHOO M18 nothing. Seat depth: the SIHOO M57 lists “18.11 in (≈46 cm)”, the SIHOO M18 “17.91 in (≈45.5 cm)”.

Other details. Headrest: the SIHOO M57 lists “Headrest adjusts vertically up to 3.9 inches and rotates 45 degrees”, the SIHOO M18 “Headrest moves 3.9" up and down and pivots 45°”. Lumbar support: the SIHOO M57 lists “Dual-adjustable lumbar support (vertical and horizontal)”, the SIHOO M18 “Lumbar support adjusts vertically and horizontally”. Chair weight: the SIHOO M57 lists “44.8 lb (≈20.3 kg)”, the SIHOO M18 “37.1 lb (≈16.8 kg)”.

Same on both. The M57 and M18 list the same recline (up to 126°), warranty (3 years) and maximum load (330 lb, ≈150 kg).

Who should buy which

• Pick the M57 over the M18 if you want armrests that move in more directions than just up and down (3D).
• Pick the M18 over the M57 if you want the lower price — the M18 lists $30 below the M57.
• Pick the M18 over the M57 if you want a lighter chair to move around: 37.1 lb (≈16.8 kg) against 44.8 lb (≈20.3 kg).

Not published by the brand (M57 vs M18): seat height and seat width for the SIHOO M18.

Sources

• SIHOO M57 (compared here with the M18): Sihoo M57 Netz Bürostuhl – DE Sihoo Offizieller Shop; SIHOO M57 Ergonomic Mesh Office Chair – Official US Sihoo Store, checked 2026-10-09; US list price from SIHOO US Official Store, checked 2026-10-09.
• SIHOO M18 (compared here with the M57): Sihoo M18 Ergonomic Office Chair – Official US Sihoo Store, checked 2026-09-29; US list price from SIHOO US Official Store, checked 2026-10-07.
• Figures marked ≈ for the M57 and M18 are Chairpedia's unit conversions, not brand figures.