Momme Count in Silk: The Complete Fabric Reference Guide
Lunelle Team
13 min read
Silk listings say things like "22 momme" and trust that you will know what it means. Most people do not, and there is no reason they should. Momme is a measurement unit from the Japanese textile industry. It never made it into general use the way thread count did for cotton.
That absence has created a category where important quality information is quietly present on listings and just as quietly ignored.
This guide explains what momme count actually means, how to read it across different silk applications, and how to use it to make a practical buying decision. It is a reference document, not a short FAQ. If you want the concise version, our guide to momme in silk pillowcases covers buying decisions specifically.
Quick Answer
Momme (mm) is the weight measurement unit for silk. It is defined as the weight in pounds of a piece of silk measuring 100 yards long by 45 inches wide. The higher the momme number, the heavier, denser, and more durable the silk. For pillowcases, Sleep Foundation recommends 19 to 25 momme, with 22 momme as the most balanced everyday choice. The full range runs from 6 momme for silk organza up to 40+ momme for upholstery applications.
Key Takeaways
- Momme measures silk fabric weight, derived from pounds per standardised sheet (100 yards x 45 inches). It is the silk equivalent of GSM (grams per square metre) used for other textiles.
- Higher momme = heavier, denser, more durable fabric. Lower momme = lighter and sheerer. Neither is universally better; the right weight depends on the application.
- For pillowcases, Sleep Foundation recommends 19 to 25 momme. 22 momme sits at the centre of this range and is the most widely recommended choice for durability and comfort.
- Momme and thread count measure different things. Thread count counts yarns per inch. Momme measures fabric weight. They are complementary metrics, not substitutes.
- Grade 6A refers to raw silk quality (fibre uniformity, purity), not momme weight. A pillowcase can be labelled Grade 6A at any momme.
What Momme Actually Means: The Technical Definition
Momme is a Japanese unit of mass. In silk, it defines the weight of a standard piece of silk fabric: one momme equals the weight in pounds of a sheet measuring 100 yards long by 45 inches wide.
In modern units: 1 momme equals approximately 4.34 grams per square metre.
That 4.34 g/m² conversion is the key to reading momme practically. A 22 momme silk fabric weighs roughly 95.5 g/m². A 30 momme fabric weighs approximately 130.2 g/m². You can calculate the approximate GSM for any momme weight by multiplying the momme number by 4.34.
For context: silk chiffon typically sits around 6 to 8 momme. Lightweight silk habotai runs 8 to 10 momme. Charmeuse for pillowcases sits between 19 and 30 momme. Upholstery and furnishing silks can reach 40 momme or higher.
Momme vs Thread Count: Two Different Measurements
Thread count came to dominate the cotton bedding market in the 1990s. It measures the number of warp and weft yarns per square inch of woven fabric. Higher thread count became synonymous with quality, even though the relationship is more complicated than that.
Momme and thread count measure completely different things. Confusing them leads to poor buying decisions.
Thread count for silk is rarely meaningful in the same way it is for cotton, for two structural reasons. First, silk filaments are much finer than cotton yarns, so two fabrics with the same thread count can feel dramatically different. Second, manufacturers can inflate thread count by counting individual strands within each yarn.
Momme is harder to manipulate in this way. It is a direct physical weight measurement. You cannot inflate a fabric's weight without putting more material in it.
| Metric | What It Measures | How to Use It | Silk Relevance |
|---|---|---|---|
| Momme | Fabric weight (g/m²) | Higher = heavier, more durable, denser | The primary quality signal for silk |
| Thread count | Yarns per inch (warp + weft) | Relevant for cotton; less meaningful for silk | Informative but less reliable than momme |
| GSM | Grams per square metre | Universal fabric weight standard (1 mm = 4.34 g/m²) | Converts directly from momme |
Our detailed comparison covers silk thread count vs momme if you want to go further on this distinction.
The Full Momme Range by Application
Silk fabric covers an enormous range of weights. A scarf made for summer heat and a curtain panel for a formal room are both silk. They would not be the same momme.
The right momme for the job depends entirely on what you are asking the fabric to do.
| Momme Range | Weight (approx g/m²) | Common Applications | Key Characteristics |
|---|---|---|---|
| 6 to 8mm | 26 to 35 g/m² | Silk organza, fine veils, overlay layers | Very sheer and lightweight; structured but delicate |
| 8 to 10mm | 35 to 43 g/m² | Habotai (China silk), linings, underlays | Soft and draping; too light for standalone bedding |
| 10 to 14mm | 43 to 61 g/m² | Lightweight scarves, bridal overlays, sarongs | Fluid drape; still translucent at lower end |
| 14 to 18mm | 61 to 78 g/m² | Lightweight blouses, dress linings, some scarves | Good drape; building toward opacity |
| 19 to 25mm | 82 to 109 g/m² | Pillowcases (Sleep Foundation recommended range) | Durable; smooth; holds up through regular washing |
| 22mm | ~95.5 g/m² | Pillowcases (recommended centre point) | Ideal balance of softness, durability, and drape |
| 25 to 30mm | 109 to 130 g/m² | Premium pillowcases, duvet covers, heavier apparel | More substantial; longer-lasting; richer hand |
| 30mm | ~130.2 g/m² | Luxury pillowcases, premium bedding | Noticeably heavier; deepens colour; maximum durability |
| 30 to 40mm+ | 130+ g/m² | Furnishing fabrics, drapery, upholstery | Heavy; less draping; engineered for wear over years |
What You Will Actually Notice at Each Pillowcase Weight
The numbers mean more once they connect to what you will feel in practice. Here is what each main pillowcase momme delivers as an experience, not just a specification.
19 Momme: The Entry Point to the Recommended Range
A 19 momme pillowcase is the lightest weight Sleep Foundation recommends for bedding. The fabric is noticeably lighter than 22 or 30 momme options. It will still feel smooth and cool, substantially different from cotton.
19 momme is where silk bedding starts. It is not where it peaks.
The tradeoff at this weight is durability. 19 momme is more susceptible to pilling, light snags, and wear over time with repeated washing. It is a reasonable starting point. It is not the best long-term choice for daily use.
22 Momme: The Most Widely Recommended Weight
Sleep Foundation cites 22 momme as sitting at the centre of the recommended 19 to 25 momme range. Most dermatologists and hair experts who recommend silk pillowcases are describing this weight, even when they do not specify it.
22 momme is the recommendation that holds across most uses, most hair types, and most budgets.
At 22 momme, the fabric is dense enough to hold up through regular machine washing on a delicate cycle. The charmeuse weave at this weight creates the smooth, low-friction surface responsible for the friction-reduction benefits referenced by the AAD and Cleveland Clinic.
25 Momme: Moving Toward Premium
At the top of Sleep Foundation's recommended range, 25 momme delivers a noticeably weightier feel. The fabric is more opaque and handles repeated washing with less wear. Colour saturation is deeper.
The difference from 22 momme is tangible but not dramatic. For most people, 22 momme is the practical sweet spot. For those who want to maximise longevity and prefer a richer feel, 25 momme is the next step within the standard recommendation.
30 Momme: The Luxury Weight
30 momme is the premium tier for pillowcases. The fabric is appreciably heavier, more durable, and richer in colour and texture. It is substantial, not lightweight and airy.
30 momme lasts longer. It does not produce better hair or skin results than 22 momme.
Sleep Foundation is clear on this distinction: improvements in beauty benefits are not proportional as you move above 25 momme. The additional investment at 30 momme buys durability and a premium experience. It does not buy meaningfully better outcomes for your hair or skin.
Choosing Between 22 Momme and 30 Momme
This is the practical decision most buyers end up with. Here is how to think about it without the marketing noise.
| Consideration | 22 Momme | 30 Momme |
|---|---|---|
| Within Sleep Foundation recommendation | Yes (centre of range) | Exceeds recommended range (25mm max) |
| Hair and skin friction reduction | Fully delivered | Equivalent benefit |
| Durability through washing | Good for regular use | Higher; outlasts 22mm over time |
| Feel | Light, smooth, cool | Weighty, substantial, rich |
| Colour depth | Good | Deeper saturation |
| Relative price | Lower | Higher |
| Best for | Daily use, most buyers | Those prioritising longevity and premium feel |
22 momme is the answer if you want the benefits with nothing to overthink. 30 momme is the answer if you want a pillowcase that will still feel exceptional five years from now and you are comfortable paying for that longevity.
Momme and the Benefits of Silk: What the Evidence Says
A common question is whether higher momme produces better hair and skin results. The evidence-based answer is: not proportionally.
The friction-reduction benefits of a silk pillowcase are well supported by dermatology sources including the AAD and Cleveland Clinic. These benefits derive from the smooth, low-friction charmeuse weave surface. That surface is adequately created by any fabric in the recommended 19 to 25 momme range.
Above 25 momme, you are buying quality and durability. You are not buying better results for your hair.
| Benefit Claim | Evidence | Momme Dependency |
|---|---|---|
| Reduces friction on hair | Well supported (AAD, Cleveland Clinic) | Delivered by any charmeuse in 19 to 25mm range |
| Reduces frizz and tangles | Well supported as a friction-reduction outcome | As above |
| May reduce sleep creases | Plausible; supported by sleep wrinkle research | As above |
| Anti-aging or collagen claims | Not supported by clinical evidence (Sleep Foundation) | Not relevant regardless of momme |
| Acne prevention | Not supported (Sleep Foundation) | Not relevant regardless of momme |
| Durability through washing | Physical property | Higher momme = more durable |
Where Momme Matters Most: The Pillowcase Buying Decision
The friction-reduction benefits of a silk pillowcase come from the smooth, continuous surface of the fabric. That surface is created by two things working together: the charmeuse weave and the momme weight.
A pillowcase that is too light in momme lacks the density to maintain its smooth surface through regular use. Below about 19 momme, the fabric is prone to pilling and wear that compromise the surface quality you bought it for.
Grade 6A and Momme: Two Separate Quality Signals
Grade 6A and momme appear together on many premium listings. They are not the same thing. They do not measure the same thing.
Grade 6A refers to raw silk quality under Chinese national grading standards (GB/T 1797-2008). It indicates fine, uniform, low-impurity filaments. It is a measure of the source material before the fabric is woven.
Momme tells you how much of that material is in the finished fabric. Grade 6A tells you how good the raw material was.
A pillowcase can be Grade 6A at 14 momme (lightweight and less durable) or Grade 6A at 30 momme (heavy and long-lasting). Conversely, a 22 momme fabric made from lower-grade raw silk will feel worse than a 22 momme fabric made from Grade 6A material. Both signals are informative. Neither replaces the other.
Weave Type: Why Charmeuse Is the Right Choice for Pillowcases
Momme measures weight. Weave type determines how the silk is constructed. Both shape the final surface a pillowcase presents.
Charmeuse is a satin weave structure: the majority of threads run along the surface with minimal interlacing. This creates the smooth, lustrous face that gives silk pillowcases their friction-reducing properties.
For a pillowcase, charmeuse is not a preference. It is the structure that creates the benefits you are buying silk for.
Habotai (also called China silk) is a plain weave, lighter, and used in linings and budget pillowcases. It is softer but less durable and produces a less smooth surface than charmeuse. Crinkle and jacquard weaves create interesting textures but are not optimal for the smooth sleep surface that delivers friction benefits.
Silk vs Satin: The Distinction Every Buyer Needs to Know
Satin is a weave. Silk is a fibre. A "satin pillowcase" can be made from silk or from polyester.
Encyclopaedia Britannica defines satin as a fabric made using the satin weave, noting it is now produced from many fibre types including polyester and nylon. This distinction matters for momme because momme is a measurement that applies to silk specifically.
If a listing does not say "100% silk" or "100% mulberry silk," the momme number on it means very little.
A polyester satin pillowcase does not have a momme weight in any meaningful sense. For a full account of this distinction, our guide to the best pillowcase for hair covers the comparison in the context of overnight hair care.
Caring for Silk at Each Momme Weight
Higher momme silk is more forgiving to wash. The additional density means the fabric is less likely to distort, stretch, or pill under mechanical agitation. The same care principles apply across all weights, though.
Cool water prevents protein fibre damage. Enzyme-free, pH-neutral detergent avoids breaking down the silk protein structure. A delicate machine cycle or gentle hand wash is appropriate. Avoid dryer heat and direct sun exposure for drying.
Hard water creates an additional challenge worth being aware of. Mineral deposits can build up on silk and affect both feel and longevity over time.
Our guide on washing silk in hard water areas covers the full solution for those in areas with high mineral content. For the complete ongoing care guide, see how to keep silk looking new.
If you have read this far, you know what to look for: the momme weight (22 for everyday use, 30 for longevity), Grade 6A raw silk, and OEKO-TEX certification.
Both Lunelle pillowcases meet all three criteria. Machine washable. Set of two. 60-night guarantee on both.
Frequently Asked Questions
What is momme in silk?
Momme (mm) is the weight measurement unit used for silk fabric. It is defined as the weight in pounds of a piece of silk measuring 100 yards long by 45 inches wide. One momme equals approximately 4.34 grams per square metre. Higher momme means heavier, denser, and more durable silk.
What momme should a silk pillowcase be?
Sleep Foundation recommends 19 to 25 momme for silk pillowcases. 22 momme is the most widely recommended weight within this range, offering the optimal balance of smoothness, durability, and comfort for everyday use. Below 19 momme, the fabric is more prone to pilling and wear.
Is 30 momme better than 22 momme?
30 momme is heavier, more durable, and longer-lasting than 22 momme. However, Sleep Foundation specifies that beauty benefits do not scale proportionally above 25 momme. 30 momme is a premium choice for those who prioritise longevity and a substantial feel, not for improved hair or skin outcomes.
What is the difference between momme and thread count?
Thread count measures the number of yarns per square inch of woven fabric. Momme measures the physical weight of the fabric per standardised sheet. For silk, momme is the more meaningful quality indicator. Thread count for silk is less informative and more susceptible to manipulation through double-counting plies.
What does 22 momme feel like?
22 momme charmeuse feels smooth, cool, and noticeably lighter than cotton. The surface has a characteristic silk sheen and drapes easily. It is dense enough to feel substantial without being heavy. Most people describe it as immediately different from any cotton or synthetic pillowcase they have used.
Is higher momme always better?
For durability, yes. For beauty benefits, no. Higher momme silk will outlast lower momme over repeated washing. But the friction-reduction benefits that dermatologists reference are delivered by any charmeuse silk in the 19 to 25 momme range. The improvements in hair and skin outcomes above 25 momme are not significant.
What is the difference between Grade 6A and momme?
Grade 6A refers to raw silk quality: the uniformity, purity, and fineness of the silk filaments under Chinese national grading standards. Momme refers to the finished fabric weight. A pillowcase can be Grade 6A at 19 momme or at 30 momme. Both signals are informative and neither replaces the other.
What momme is good for silk scarves?
For lightweight, draping scarves, 10 to 14 momme is typical. Heavier, more structured scarves may range from 14 to 18 momme. The right weight depends on how the scarf is intended to drape and wear. Scarves are generally much lighter than pillowcase silk.
What momme is silk organza?
Silk organza typically runs between 6 and 8 momme. This produces a sheer, structured fabric with a crisp hand. It is far lighter than pillowcase silk and is used in overlays, bridal wear, and decorative applications rather than bedding.
Does higher momme silk last longer?
Yes. A heavier momme fabric has more material in the weave, which gives it greater resistance to abrasion, pilling, and wear through washing. Sleep Foundation notes this as a practical benefit of choosing towards the higher end of the recommended range, distinct from any beauty benefit.
How do I convert momme to grams per square metre?
Multiply the momme number by 4.34 to get the approximate weight in grams per square metre. A 22 momme fabric weighs approximately 95.5 g/m². A 30 momme fabric weighs approximately 130.2 g/m². This conversion is the same across all silk types.
Is satin the same as silk?
No. Satin is a weave structure; silk is a fibre. A satin pillowcase can be made from silk filaments or from polyester fibres. Momme is relevant only to real silk. If a listing says "satin" without specifying "100% silk" or "100% mulberry silk," it is likely synthetic.
Further Reading
The buyer-focused guide to momme weight specifically for pillowcase decisions, including which weight to choose and why.
Read more →A detailed comparison of the two main silk quality metrics, and how to use them together rather than treating them as alternatives.
Read more →The complete explanation of mulberry silk: fibre type, production, what sets it apart from other silks, and what to look for when buying.
Read more →The complete guide to choosing a pillowcase for reduced breakage, frizz, and overnight friction, including the silk vs satin distinction.
Read more →The complete washing guide for silk pillowcases: water temperature, detergent choice, machine vs hand wash, and drying.
Read more →How hard water affects silk and what to do about it: water softening, vinegar rinses, and distilled water for final rinses.
Read more →Sources and References
- Sleep Foundation. Benefits of a Silk Pillowcase. sleepfoundation.org
- American Academy of Dermatology. 6 Curly Hair Tips from Dermatologists. aad.org
- Cleveland Clinic. Is Sleeping on a Silk Pillowcase Better for Your Skin and Hair? health.clevelandclinic.org
- CAMEO, Museum of Fine Arts Boston. Silk. cameo.mfa.org
- Encyclopaedia Britannica. Satin. britannica.com
- Encyclopaedia Britannica. Silk. britannica.com
- PubMed. Sleep Wrinkles: Facial Aging and Facial Distortion During Sleep. pubmed.ncbi.nlm.nih.gov
- National Institutes of Health, PMC. A Laboratory-Based Study Examining the Properties of Silk Fabric. pmc.ncbi.nlm.nih.gov
- ApparelX News. Grades of Silk: Grade 6A, the Best Quality Silk. apparelx-news.com
- National Institutes of Health, PMC. Hair Cosmetics: An Overview. pmc.ncbi.nlm.nih.gov