Momme (もんめ) is the unit that defines silk weight — and the easiest way to tell quality silk from filler-grade. This guide covers what momme means, why it matters for pillowcases, sleepwear and bedding, and how to choose the right grade.
What is momme?
Momme is a Japanese weight measurement borrowed by the silk industry. One momme equals the weight in pounds of a piece of silk 45 inches wide and 100 yards long. Higher momme = denser, heavier, longer-lasting silk. The number you see on a silk product (16mm, 19mm, 22mm) is its momme weight.
Momme grades — what each means in practice
| Momme | Weight (g/m²) | Typical use | Price tier |
|---|---|---|---|
| 6–8mm | ~26 g/m² | Linings, scarves | Entry |
| 12mm | ~51 g/m² | Light blouses | Affordable |
| 16mm | ~68 g/m² | Mass-market pillowcases (Slip, Brooklinen base line) | Mid |
| 19mm | ~81 g/m² | Premium pillowcases, light pajamas | Premium |
| 22mm ⭐ | ~93.5 g/m² | Luxury pillowcases, full pajamas, bedding (Rêvery & Silk) | Luxury |
| 25mm | ~106 g/m² | Heavy bedding, formal pajamas | Ultra-luxury |
| 30mm | ~127 g/m² | Couture, rare bedding | Couture |
Why 22-momme is the sweet spot for sleep and skin
- Drape: at 22mm the silk drapes against the skin without feeling stiff (a problem above 25mm) or thin (16mm shows the pillow texture through it).
- Lifespan: 22mm silk withstands ~10 years of weekly washing when cared for properly; 16mm starts pilling at year 3.
- Friction: the same 43% friction reduction vs cotton (Yonzon et al., 2020) requires at least 19mm — 16mm silk loses much of that benefit.
- Thermoregulation: 22mm is thick enough to hold body heat in winter without overheating in summer — the unique fibre structure breathes.
What momme alone does not tell you
Momme is necessary but not sufficient. Also check:
- Grade (1A → 6A): refers to fibre length. Grade 6A is the longest, smoothest fibre — what we use exclusively.
- Origin: mulberry silk (Bombyx mori, fed on Morus alba leaves) is the gold standard. Wild / tussah silk has less luster and is coarser.
- Certification: OEKO-TEX Standard 100 tests for harmful substances. Without it, dyes and finishes may contain heavy metals or formaldehyde.
- Weave: charmeuse (satin weave) is the silkiest. Habotai is lighter and matte. Crepe is textured.
How to verify the momme of a silk product before buying
- Look for the momme number on the product page (e.g., "22 momme"). If absent, assume 16mm or lower.
- Check the weight per m². Below 80 g/m² = under 19mm. Above 90 g/m² = 22mm+.
- Ask for the Grade letter (1A → 6A). Grade 6A is the longest-strand.
- Demand OEKO-TEX Standard 100 certification with a certificate ID.
FAQ
Is higher momme always better?
Up to a point. 22mm is the practical maximum for pillowcases and sleepwear — heavier silk feels stiff and traps too much heat. 25mm+ is reserved for ceremonial garments or formal bedding.
What does "momme" mean exactly?
It's a Japanese weight unit. One momme = 3.75 grams. In silk, the convention measures a 45-inch wide × 100-yard long piece in pounds. A 22-momme silk weighs 22 pounds at those dimensions, which equates to about 93.5 g/m².
Is 22-momme silk worth the extra cost?
For pillowcases and pajamas you'll use nightly, yes. The lifespan triples vs 16mm, and the friction-reduction and thermoregulation benefits scale with momme. The cost-per-night over 10 years drops below cotton at the luxury tier.
Where is Rêvery & Silk's silk made?
Designed in France, woven in Hangzhou — historically the silk capital of China since the 12th century. All pieces are OEKO-TEX Standard 100 certified.
Browse 22-momme silk pieces
- The Signature Pillowcase — 22mm, 8 colors
- Silk Sleepwear collection — 5 styles, 22mm
- The Silk Bed Linen Set — full bed, 22mm, 10 colors