The single most important number on a silk spec sheet, and the one most often misunderstood. A wholesale buyer's reference.
Momme — pronounced "mommy," sometimes abbreviated to mm — is the standard unit for measuring the weight, and therefore the density and quality tier, of silk fabric. One momme equals approximately 4.34 grams per square metre. A 22-momme silk weighs about 95 g/m². The higher the number, the denser the weave, the more silk fibre per unit area, the longer the piece will last.
For wholesale buyers of silk bedding, three weights matter:
Below 19 momme is fashion territory (scarves, blouses) — too light for bedding. Above 25 momme exists (30+ momme charmeuse, brocade weaves) but the price-to-perceptible-quality jump becomes hard to justify in bedding outside the very top tier.
The momme system originates in Japan. It is a weight-per-area measurement, not a thread count. This matters because thread count is misleading for silk — a high thread count of fine yarns can produce a flimsy fabric, while a moderate thread count of heavier yarns produces a substantial one. Momme captures the substance directly.
The momme number tells you how much silk is in the fabric. Everything else — thread count, ply, weave — is downstream of that.
Too light for bedding in our view. Some entry-level brands market 16-momme pillowcases as "silk pillowcases" at low price points; they tend to wear out within 18 months of weekly laundering. We do not stock below 19 momme.
The acceptable entry tier. Light, smooth, breathable. Reasonable for warm climates and for customers testing silk for the first time. Lifespan with proper care: roughly 3–5 years. Used in our standard sheet sets.
The market default. The right balance of substance, drape, breathability, lifespan and cost. Roughly 70% of silk pillowcase wholesale globally is 22 momme. Lifespan with proper care: 5–8 years. Our default for pillowcases and the heavier sheet sets.
The luxury / hospitality weight. Denser, more lustrous, with a noticeable drape difference. Built for commercial laundering and frequent use. Lifespan with proper care: 8–12 years. We stock 25-momme pillowcases, duvet covers and selected hospitality SKUs.
Exists for couture and the very top end of bedding. We can source on bespoke runs but do not stock — the price step does not match the perceptible quality step for most retail customers.
On a wholesale purchase order, momme should always be written as a number followed by "mm" or the word "momme." Specify it for every silk component of a multi-piece set. A common error is to specify the duvet cover at 25 momme and let the pillowcases default to 22 — they will look subtly different at the bed.
Buyer's tip: when comparing supplier quotes, always ask momme weight first. A 19-momme pillowcase from one supplier and a 22-momme from another are not the same product at all — and the price difference of $1.50 per unit at the supplier translates to a $15 retail price separation.
Momme tells you the substance. It does not tell you:
Use momme as the first filter, then layer the other questions. That is what your supplier should be ready to answer.