Methodology
How We Rate Office Chairs
Every chair gets an Ergo Score (0 to 100) for adjustability, support and build, and a separateComfort Index (0 to 100) for how it should feel to sit in. Both come from listed specifications with one formula for every chair. The same inputs always give the same score. We have not physically tested these chairs.
Ergo Score
Three pillars add up to 100. A feature the seller does not list scores 0 and shows as "Not listed by the seller"; nothing is credited unless the data states it.
Adjustability (up to 40 points)
Task chairs only (home office, managerial and executive, gaming, drafting).
| Line | Maximum | How points are awarded |
|---|---|---|
| Armrests | 10 | 4D 10, 3D 8, 2D 6, 1D 3, fixed or flip-up 1, none 0 |
| Seat height | 6 | Adjustable 4, plus 2 when the listed range is at least 4 inches |
| Seat depth | 5 | Seat depth adjustment 5 |
| Lumbar adjustment | 7 | Height 3, depth 2, tension 2 |
| Recline | 2 | Backrest reclines to 100 degrees or more 2 |
| Tilt lock | 3 | Stated tilt lock 3 |
| Tilt tension | 3 | Adjustable tilt tension 3 |
| Advanced tilt | 4 | Synchro tilt, weight-sensing recline, knee tilt, flexing back or self-adjusting tilt 4 |
| Total | 40 |
Support (up to 30 points)
| Line | Maximum | How points are awarded |
|---|---|---|
| Lumbar support | 12 | Lumbar support present 8, plus 4 when a named mechanism or adjustment is stated |
| Upper back support | 4 | Backrest at least 25 inches tall, or a headrest, 4 |
| Headrest adjustment | 2 | Adjustable headrest height or angle 2 |
| Cushion | 5 | Memory foam, high-density foam, molded foam or mesh seat 5 |
| Seat edge | 3 | Waterfall or flexible edge 3 |
| Breathable back | 4 | Mesh or knit back 4 |
| Total | 30 |
Build (up to 30 points)
| Line | Maximum | How points are awarded |
|---|---|---|
| Warranty | 9 | 10 years or more 9, 5 to 9 years 6, 2 to 4 years 3, 1 year 1 |
| Weight capacity | 6 | 300 lb or more 6, 250 to 299 lb 4, under 250 lb 2 |
| Certifications | 5 | BIFMA 4, any other listed certification 1 |
| Base | 3 | Aluminum 3, steel or metal 2, nylon 1, plastic 0 |
| Gas lift | 2 | Class 4 gas lift 2, Class 3 gas lift 1 |
| Owner rating | 5 | Only with 100 or more reviews: 4.5 stars or more 5, 4.2 to 4.49 3, 4.0 to 4.19 1 |
| Total | 30 |
Pillar maxima: Adjustability 40, Support 30, Build 30, for a total of 100.
Basic chairs (guest, reception, stacking, school chairs and step stools) are scored on Support and Build only, out of 60, and are never included in the ranked lists.
Comfort Index
A separate measure of how a chair feels, shown beside the Ergo Score. The parts add up to 100.
| Part | Maximum | How points are awarded |
|---|---|---|
| Cushion | 20 | Memory foam 20, high-density or molded foam 16, mesh seat 14, other foam or sponge 8 |
| Cushion thickness | 5 | 3 inches or more 5, 2 inches or more 3 |
| Recline depth | 15 | 135 degrees or more 15, 120 or more 10, 105 or more 5 |
| Breathability | 15 | Mesh or knit back 15, fabric 8, leather or PU 4 |
| Headrest | 10 | Headrest present 10 |
| Arm comfort | 10 | Padded or adjustable armrests 10 |
| Owner rating | 25 | Rating scaled from 3.5 to 5.0 onto 0 to 25, weighted down when there are few reviews |
| Total | 100 |
Tiers
The tier is the Ergo Score as a percent of the maximum for the chair's profile.
| Tier | Ergo Score |
|---|---|
| Excellent | 56 percent or more of the maximum |
| Very Good | 46 to 55 percent |
| Good | 36 to 45 percent |
| Fair | 25 to 35 percent |
| Basic | under 25 percent |
Data Coverage and the Limited Data Badge
Data coverage is the share of 20 scoring-relevant specification fields that are filled for a chair, as a percent. A chair under40 percent coverage carries a "Limited data" badge, because its score is mostly the absence of listed specs rather than a measured weakness. Limited data chairs are left out of the ranked lists. Every missing spec shows on the chair's page as "Not listed by the seller".
Where Specifications Come From
- The Amazon.com listing for the chair, including its product details.
- The manufacturer's own product or specification page, only for the exact model we list.
- Gaps are filled only where a spec is blank, never overwriting an existing value, and the page marks such values "from manufacturer" or "from Amazon listing".
- Quote verification: every filled value must be backed by a quote that appears word for word in the saved source page, and numbers must appear in that quote. Customer reviews, questions and answers, other retailers and review sites are never used.
Chair Fit Calculator and Fit Guide
Both use the rule of thumb that the ideal seat height is one quarter of your height (the rule ergochairs.in uses, also published by the Omni Calculator chair height calculator). A 5 ft 10 in person (70 in) gets a target of 17.5 in. A chair is a good fit when its listed seat height range contains the target and, where the seller lists one, its weight rating covers you. Chairs with no listed seat range are not matched.
Availability
We only list chairs you can buy on Amazon.com right now. Availability and prices are rechecked regularly; a chair that is unavailable or cannot be confirmed is removed, and when it returns its page comes back. Scores never change because a chair comes or goes.
What We Never Do
- We never credit a feature the seller does not list, and we never estimate a missing spec.
- No payment or commission changes a score or a ranking. Sponsored placements, if any, are always labelled "Sponsored".
- Rankings describe what a chair offers on paper, not how it feels after a long day. A better chair can help posture and comfort; it is not a medical treatment.
Frequently Asked Questions
Why is a chair I saw before not listed?
We only list chairs you can buy on Amazon.com right now. We recheck regularly; when a chair returns, its page comes back.
How often are prices and ratings updated?
Prices and availability come from Amazon.com and are rechecked regularly; the date of the latest check is shown next to every price. Specifications are verified against the Amazon listing and the manufacturer, and scores are recalculated whenever the specifications change.
How do the Ergo Score and Comfort Index work?
The Ergo Score rates adjustability, support and build from listed specifications, using the same published formula for every chair. The Comfort Index rates cushioning, recline, breathability, headrest, armrests and owner rating. When a seller does not list a feature, the chair gets no points for it; we never estimate. See How We Rate for the full breakdown.
Do you test the chairs in person?
No. We have not physically tested these chairs. Scores come from manufacturer and Amazon specifications, so they describe what a chair offers on paper, not how it feels after a long day. A better chair can help posture and comfort; it is not a medical treatment.
Questions or Corrections
Think a spec or score is wrong? Email ergnometry@gmail.com with the chair's name and we will look into it.