What Is SIHOO?
SIHOO is an ergonomic seating specialist — and notably, ergonomic chairs are effectively all it makes. The brand has spent 15 years refining one product category, and that focus shows. It ships to 122+ countries and sells more than 1.9 million products worldwide each year, with over 513,000 reviews left across Amazon, Reddit, and Trustpilot. Its chairs carry BIFMA and TUV certification and support up to 330 lb, backed by a 3-year warranty and 30-day returns.
SIHOO describes itself as "the world's leading ergonomic chair brand," and its products are featured in more than 2,000 media outlets a year. You can read the full story on the official SIHOO site.
For U.S. shoppers, SIHOO's direct-to-consumer store is the place where the full lineup lives — including the newest B-series and the flagship Doro series. Unlike a marketplace listing, the DTC store carries every colorway, the footrest versions, and the newest releases that haven't hit every retailer yet.
How we researched this guide
Refer a Deal is a research desk, not a test lab. We do not claim to have assembled or used these chairs, and nothing here is written as if we did. What we did instead: pulled the specifications and prices from the official sihoo.com product and collection pages, and cross-checked them against independent coverage from TechRadar, Tom's Guide, Forbes, CNET, and CNN. Every figure in the spec table below traces back to one of those sources. Where the official page doesn't publish a value, we leave a dash rather than close the gap. You can read more about how we approach every guide on our method page.
The SIHOO Lineup at a Glance
SIHOO's DTC store sells thirteen chair products, spread across four price tiers from $169.99 to $599.99. The chart below maps every model, with the flagship Doro series highlighted in red.
The Three Series, Explained
Thirteen SKUs can look like a wall of chairs, but SIHOO's lineup is really just three series with a clear hierarchy. Once you know the code, you can skip straight to the two or three chairs that fit you.
- Doro series (flagship). This is where SIHOO puts its real engineering — C300, C300 Pro, C300 Pro V2, S300, and S100. Adaptive and "dynamic" lumbar systems, 4D–6D armrests, and the brand's most advanced recline mechanisms. If SIHOO wins an award, it's usually for a Doro.
- B series (2026 budget line). The newest addition — B100, B100 Pro, and B300 Pro. Built to bring ergonomic basics down to the $199–$260 range without the premium mechanisms of the Doro line.
- M series (classic value). The workhorses — M18, M57, and M59AS. The M18 and M57 are SIHOO's long-running bestsellers, with the M57 (full mesh, 330 lb) and M59AS (flip-up arms, space-saving) covering the most common real-world use cases.
Two Doro models also come in footrest versions — the C300 Footrest ($329.99) and C300 Pro Footrest ($409.99) — which bolt a retractable leg rest onto the standard chair for reclining breaks. They're listed separately on the site, which is why the "13 products" count is slightly higher than the ten core models.
Price Bands
SIHOO's DTC pricing is deliberately simple — the lineup climbs from $169.99 to $599.99 with no filler in between. It breaks into four clean bands:
SIHOO Ergonomic Chairs Compared: Full Spec Table
Every model side by side, using the criteria that matter most when buying an ergonomic chair: lumbar support, armrests, recline, weight capacity, and warranty. A dash (—) means the spec isn't published on the official product page.
| Model | Series | Sale price | List price | Lumbar support | Armrests | Recline | Capacity | Warranty |
|---|---|---|---|---|---|---|---|---|
| M18 | M | $169.99 | $289.99 | Dual (adjustable) | Height-adjustable | 126° | 330 lb | 3 yr |
| B100 | B | $199.99 | — | — | — | — | — | 3 yr |
| M57 | M | $239.99 | $319.99 | Dual (adjustable) | 3D | 126° | 330 lb | 3 yr |
| M59AS | M | $239.99 | $449.99 | Dual-section back | 3D flip-up | — | — | 3 yr |
| B100 Pro | B | $259.99 | — | — | — | — | — | 3 yr |
| B300 Pro | B | $259.99 | $329.99 | — | — | — | — | 3 yr |
| Doro C300 | Doro | $279.99 | $559.99 | Self-adaptive | 4D | 130° | 300 lb | 3 yr |
| Doro S100 | Doro | $299.99 | $499.99 | Dual dynamic | 4D | 135° | 300 lb | 3 yr |
| C300 Footrest | Doro | $329.99 | $609.99 | Self-adaptive | 4D | — | — | 3 yr |
| Doro C300 Pro | Doro | $359.99 | $789.99 | Adaptive | 4D | — | — | 3 yr |
| C300 Pro Footrest | Doro | $409.99 | $839.99 | Adaptive | — | — | — | 3 yr |
| C300 Pro V2 | Doro | $429.99 | $499.99 | Domino™ sacral-lumbar | 6D | — | — | 3 yr |
| Doro S300 | Doro | $599.99 | $999.99 | 6D floating wing | 6D | 100°–130° | — | 3 yr |
Prices are sihoo.com sale prices (standard version) at the time of writing; footrest versions and color variants are listed separately. SIHOO advertises a 3-year warranty and 30-day returns across the lineup. The C300, C300 Pro V2, and S300 rows are highlighted as our top picks. Capacity figures come from SIHOO's own product pages (300 lb for the C300 and S100, 330 lb for the M18 and M57); a dash marks values the official page does not list.
Top Picks by Need
Deep Dive: The Doro Series
If you remember one thing from this guide, make it this: the Doro series is SIHOO's flagship line, and it's where the brand actually competes with Herman Miller and Steelcase on ergonomics — at a fraction of the price. Five chairs share the same DNA (adaptive lumbar, 4D+ armrests, weight-sensing or anti-gravity recline) while stepping up in adjustability. Four of them are worth a close look.
The chair SIHOO is best known for — and its best-seller, with 997 reviews on the official store alone.
- Self-adaptive lumbar support that moves with your lower back as you shift.
- 4D adjustable armrests plus a multi-adjustable headrest.
- Weight-sensing recline that balances automatically for effortless posture changes.
- Breathable mesh and a waterfall seat edge, rated for up to 300 lb.
- BIFMA & TUV certified, endorsed by Tom's Guide, CNET, CNN, TechRadar, and Forbes.
SIHOO's current flagship — marketed as "the first full-body adaptive ergonomic chair," and the model tech reviewer Jon Rettinger filmed a deep-dive on.
- Domino™ sacral-lumbar support — a split system that follows both your lower back and sacral area.
- SyncroFlex™ glide system — the backrest glides as you lean, so support never drops behind you.
- 3D wide headrest and 4-zone tracking comfort (back, lumbar, sacral, seat).
- 6D coordinated armrests for fine-grained positioning.
The top of the lineup — a chair built around two flagship systems that target leg pressure and deep recline comfort.
- Anti-gravity recline with stable set angles (100°/110°/130°) that feel "weightless" yet supported.
- 6D floating-wing lumbar — butterfly-wing elements that move independently with your spine.
- 6D armrests for typing, mousing, gaming, and reclined positions.
- German Design Award 2023 winner.
The value entry into the Doro series with a taller, deeper build — SIHOO markets it as the ergonomic chair for taller people and gamers.
- Dual dynamic lumbar support for consistent lower-back contact.
- 4D armrests and a multi-adjustable headrest.
- 135° recline — the deepest in the lineup.
- Breathable mesh and waterfall seat, rated for up to 300 lb.
The C300 Pro ($359.99) sits between the C300 and the V2 — it adds seat-depth adjustment for long sitting and taller legs, and is the pick if you want the C300's comfort with more adjustability but don't need the V2's newest mechanisms. Both the C300 and C300 Pro also come in footrest versions (add a retractable leg rest) for $329.99 and $409.99 respectively.
Awards & Media Recognition
SIHOO's focus on a single category has earned it a surprising amount of independent attention for a value brand.
Frequently Asked Questions
What is SIHOO's flagship series? ▾
Which SIHOO chair is best for most people? ▾
What's the difference between the C300, C300 Pro, and C300 Pro V2? ▾
Which SIHOO chair is best for tall people? ▾
Which SIHOO chair is best on a budget? ▾
Is SIHOO a good brand? ▾
What warranty does SIHOO offer? ▾
Where should I buy SIHOO chairs? ▾
Where to Buy SIHOO Ergonomic Chairs
The DTC store is the primary home of the full lineup; Amazon carries many of the same models if you prefer marketplace checkout. Prices and availability shift, so compare before you check out.
Amazon links are affiliate links. We may earn a commission from qualifying purchases at no cost to you. Prices and availability are checked at the time of writing and may change.
Start with the Doro C300
SIHOO's DTC lineup is a study in focus: three series, thirteen products, and a clear flagship line that punches well above its price. The Doro C300 is the chair most buyers should choose — adaptive lumbar, 4D armrests, and a weight-sensing recline at $279.99.
For long hours, step up to the C300 Pro V2; for lounge-style recline without losing support, the S300 is the premium pick; and for height and recline on a budget, the S100 fits the bill. If you're just getting started, the M18 and M57 are proven budget workhorses.
View the Doro series on sihoo.com →