CASHMERE KNOWLEDGE · FIBER SCIENCE SERIES
What is the difference between Grade A and Grade B cashmere?
Grade A averages 14–15.5 microns in fiber diameter with fibers 34 mm or longer. Grade B runs 15.5–19 microns with 28–34 mm fibers. Grade A feels softer, resists pilling far better — because long fibers anchor securely inside the yarn — and costs roughly 1.5–2× more per kilogram. The trap to know: a "100% cashmere" label certifies the fiber type, not the grade, so a pilling sweater can still be legally "100% cashmere." Specify micron range, staple length and ply in writing when you brief a factory.
Same fiber name, different garments: Grade A (left) stays smooth for seasons; short-staple fiber (right) fuzzes and pills within weeks.
What "Grade" Actually Measures: Two Numbers
Cashmere is commercially graded A through C, and the entire system rests on two measurements you can put on one line of a spec sheet:
- Fiber diameter (microns): one micron is one-millionth of a meter. Finer fibers are softer against skin and spin into smoother yarn. This is the single most important softness indicator.
- Staple length (millimeters): the length of the individual fibers. Longer fibers spin into stronger yarn with fewer loose ends — which is the physical basis of pilling resistance and garment lifespan.
Everything a buyer experiences — softness on first touch, how the knit looks after ten wears, whether the garment still looks new next season — traces back to those two numbers. Grade is also influenced by crimp (natural wave, which gives elasticity and loft) and color (white fiber accepts dye most cleanly), but microns and length are what a spec sheet states and a lab verifies.
Under magnification, the two numbers become visible: fine, long fibers versus thicker, shorter ones.
The Three Grades Side by Side
There is no single universal grading authority — regions and mills add subgrades like A+ or B+ — but the commercial standard used across the industry converges on this:
| Grade | Fiber diameter | Staple length | Yarn cost (per kg) | Typical use |
|---|---|---|---|---|
| Baby cashmere | 13–14 µm | 40+ mm | €200–320 | Ultra-luxury sweaters, shawls |
| Grade A | 14–15.5 µm | 34–36+ mm | €140–220 | Premium sweaters, long-wear hero pieces |
| Grade B | 15.5–19 µm | 28–34 mm | €90–140 | Mid-luxury sweaters, blends |
| Grade C | 19+ µm | Under 28 mm | €55–90 | Budget blends, entry-level "cashmere" garments |
Two facts give the table its commercial weight. First, only around 30% of the raw cashmere combed globally each year meets Grade A specifications — scarcity, not marketing, is the root of the premium. Second, the grade difference flows all the way to garment pricing: a 100% Grade A pullover wholesales around $45–75 depending on gauge and weight, versus $28–48 for a Grade B equivalent — while blends built on Grade C fiber can drop below $15.
Why Micron Count Drives Softness
The biology is simple: the human itch threshold sits around 30 microns. Above it, a fiber is stiff enough to press into skin and trigger prickle; below it, the fiber bends before it can prick. All true cashmere sits comfortably under the threshold — that's why "cashmere doesn't itch" is a physical fact, not a slogan.
But within the cashmere range, every micron matters. A 14.5-micron Grade A fiber bends about twice as easily as a 19-micron fiber at the ceiling of the legal definition. That is why Grade A feels like nothing on the neck while borderline fiber feels merely "soft" — and why two garments both labeled 100% cashmere can sit three retail tiers apart.
What this looks like at Ewsca: our top grade — baby cashmere from Inner Mongolia's western grasslands — averages 13–14 microns with a 34–36 mm staple, spun from 2/26Nm to 2/48Nm yarn counts. That's the top two rows of the table above, from the source region that produces the world's finest fiber.
Why Fiber Length Decides Whether It Pills
Pilling is the number one reason customers return cashmere — and it is fundamentally a fiber-length problem, not a knitting problem.
The mechanism: when yarn is spun, each fiber must be gripped by the twist at both ends. A 36-mm fiber anchors deep in the yarn structure; a 28-mm fiber barely holds on. Under normal wear friction — a bag strap, a seatbelt, arms crossing — the loose ends of short fibers get pulled out of the knit surface, where they tangle with each other into pills. Long-staple fibers stay locked inside the yarn, so there's nothing to pull loose.
This is why the grade table pairs micron counts with length so strictly, and why "shorter fibers cannot anchor securely within the twisted yarn structure" is the single most useful sentence a buyer can know. It converts pilling from a mystery into a spec you can write: 34 mm+ staple length for garments meant to last.
One honest caveat from the factory floor: all cashmere pills eventually. Even Grade A knit shows light pilling in high-friction zones after heavy wear — it's a natural behavior of any short-staple luxury fiber versus continuous filament. The grade decides whether that happens after three years or three weeks, and proper care (resting the garment 24 hours between wears, washing instead of dry-cleaning when appropriate) slows it further either way.
The Label Law Trap: "100% Cashmere" Doesn't Mean Good Cashmere
Here is the gap between the label and the product that costs buyers the most money. Under US federal trade rules, fiber sold as "cashmere" must average no more than 19 microns, with no more than 3% of fibers over 30 microns and a coefficient of variation no greater than 24%.
Read that ceiling against the grade table: the legal maximum is the bottom of Grade B. A sweater knitted from short, borderline-diameter fiber — Grade C material that barely squeaks under the definition — can carry the exact same "100% cashmere" label as a baby-cashmere garment retailing five times higher. The label certifies the fiber type, never the grade.
Blended or mixed-grade lots make it murkier still: some suppliers blend multiple grades — or blend cashmere with other fibers — while still displaying "100% cashmere." And recycled cashmere, reprocessed from post-consumer garments and factory scraps, has shorter staple and weaker softness than virgin fiber but may appear in budget "cashmere" accessories without obvious disclosure.
The fix is one sentence: when you brief a supplier, write "Grade A cashmere, average micron X, staple length Y mm, 2-ply" — not just "cashmere." A factory that can't state micron and length for its own yarn is telling you it doesn't know, or doesn't want you to.
How to Verify Grade Before You Order
Professional verification: fiber-content certificates, third-party testing, and mechanical rub cycles — not the label.
Three professional signals separate a real grade claim from a marketing one:
- The fiber-content certificate. Ask the mill or factory for a certificate stating average micron and staple length for the yarn on offer. Reputable spinners provide it on request; hesitation is an answer in itself.
- Third-party lab testing. SGS or Intertek can confirm fiber content against claims (ISO 1833 protocols and similar). For any order big enough to matter, this is cheap insurance.
- The test swatch. Request a physical yarn sample and knit a swatch. Grade A yarn feels notably smoother, and swatches pill visibly less after 20 mechanical rub cycles — a difference you can see in an afternoon, before any deposit moves.
For quick field checks when you're holding a garment, five low-tech tests beat any label:
- The stretch test: gently stretch a section. Quality cashmere springs back within seconds; fabric that sags indicates weak or heavily blended yarn.
- The rub test: rub with your palm for 5–10 seconds. If fibers shed or pills form immediately, the staple is short or the blend is heavy.
- The warmth test: hold it against your wrist. Genuine cashmere feels warm within seconds; acrylic and cotton feel neutral or cool.
- The weight test: cashmere should feel notably lighter than it looks. Dense heaviness suggests wool content or coarse fiber.
- The price test: genuine Grade A 2-ply cannot be manufactured and shipped for under roughly $40 FOB. If the price says Grade C, the fiber is Grade C.
Which Grade Does Your Brand Actually Need?
The honest factory answer: not every brand needs Grade A, and pretending otherwise wastes margin. Match the grade to the product's job:
| If your product is… | Specify… | Why |
|---|---|---|
| A hero piece your brand is known for ($250+ retail) | Grade A or baby cashmere, 2-ply | Hand feel and multi-season pilling resistance justify the price and protect reviews |
| Core-price sweaters ($120–250 retail) | Grade A/B, 2-ply | The largest commercial tier; well-knitted Grade B is credible for years of wear |
| Entry-luxury with healthy margins | Grade A/B cashmere blended with merino | Keeps most of the softness, adds durability, lands at accessible price |
| Promotional or accessory lines | Blends, honestly disclosed | Grade C belongs in disclosed blends — not hidden behind a 100% label |
Two purchasing rules that hold across every tier: always confirm the grade in writing before production (substitution between quote and delivery is the classic fraud in this category), and remember that white and light-color fibers are the most valuable — they accept dye cleanly and give accurate Pantone matches, which matters if your brand runs specific colors.
Ewsca insider note: we publish our yarn specs because a buyer who knows what to ask for is a buyer worth supplying. Every Ewsca order states grade, micron average and staple length on the quotation — and when a client's price point genuinely doesn't need baby cashmere, we say so and spec Grade A/B instead. A supplier who only ever sells you "the best" is selling you margin, not fiber.
Frequently Asked Questions
Is Grade B cashmere bad quality?
No — it's the largest commercial tier and the backbone of mid-luxury knitwear. Well-knitted Grade B is often indistinguishable from Grade A in the first few wears; the difference shows up over months, in earlier pilling and faster softness loss. For core-price products at $120–250 retail, it's frequently the right spec. Bad quality is Grade C sold as if it were A.
What is baby cashmere, exactly?
Fiber from the first combing of young goats (under about a year old), running 13–14 microns with 40 mm+ staple — the finest commercial tier, produced in very limited volume. It's roughly 20% finer than standard Grade A and correspondingly softer and rarer. It earns its price on hero pieces and shawls, not on everyday program styles.
Can pilling be fixed once it starts?
Managed, yes — removed, carefully, with a cashmere comb or fabric shaver (never a razor). But pilling can't be prevented after the yarn is chosen, because it's determined by fiber length. The only real fix happens before production: specify staple length. See our care guide for the comb technique and the 24-hour rest rule between wears.
Does a higher price always mean a higher grade?
Usually, but not always — brand markup and retail positioning distort price. The reliable signals are the spec sheet (microns and length), third-party testing, and the price floor: below ~$40 FOB for "Grade A 2-ply," the math stops working and the fiber almost certainly isn't what the label says.
Where does grade come from — the goat or the processing?
Both. Genetics, goat age and the harshness of the climate set the raw fiber's diameter (which is why Inner Mongolia's extreme continental climate produces the finest undercoat), while sorting and dehairing determine whether that potential survives into the yarn. Only 30–50% of a goat's combed yield survives dehairing to become usable premium fiber — the rest is lost in processing.
Do certifications guarantee grade?
No — certifications cover different things. OEKO-TEX covers chemical safety, BSCI/SMETA cover labor standards, SFA and GCS cover sourcing ethics and animal welfare. Grade is a fiber measurement, verified by micron analysis and lab testing. You need both: certifications for your compliance story, spec sheets for your quality.
About the Author
The Ewsca Cashmere Team — Ewsca is a custom cashmere knitwear manufacturer with 20+ years of experience, founded in the USA with its own factory in China. We knit 100% cashmere and wool–cashmere blends from traceable Inner Mongolian yarn — baby cashmere grade at 13–14 microns — on 100+ computerized machines (3GG–14GG), with monthly capacity of 100,000+ pieces and MOQ from 100 pcs. Certified by BSCI, OEKO-TEX, INTERTEK, SFA and Organic EU. Every Ewsca quotation states grade, micron average and staple length — this guide is the standard we hold ourselves to.
Ask Us for the Spec Sheet
Tell us your retail price point and product role — we'll reply with the grade, micron count and staple length we'd spec for it, plus yarn options, pricing and a sampling plan. MOQ from 100 pcs/style/color.
Sources & References
- IMField Cashmere — When Should Retailers Order Cashmere for the Fall and Winter Season? (grade table, staple length and pilling mechanism, seasonal gauge planning)
- TextileTuts — What Is Cashmere Fabric? Properties, Grades, and Worth (A–C grading, US labeling limits, virgin vs. recycled cashmere)
- Portugal Clothing Factory — What Is Cashmere? Complete Guide for Fashion Brands (2026) (yarn cost per kg by grade, CCMI 30% Grade A supply figure, grade verification methods)
- Gobi Cashmere — Facts About Cashmere (origin data, five practical quality tests, goat yield and dehairing losses)
- FashionHDL — Cashmere Sweater Grading System: Quality Tiers Explained for B2B Buyers (grade definitions, wholesale pricing by grade, substitution risk)
Grade boundaries and yarn cost ranges are industry-published conventions and vary slightly by region and mill; the US labeling limits cited are from federal trade regulations. Ewsca-specific figures (baby cashmere microns, staple lengths, yarn counts) are from our own sourcing specifications. Verify final specs in writing with your supplier before ordering.
