Value Village ／ Clothing
This answer is a draft. It stays unpublished until legal review and source verification are complete.
"They got tight after one wash" and "the size on the label means something different in every brand" are complaints heard worldwide. Japanese denim from Okayama and Hiroshima is known internationally, and Japan has a strong culture of raw (unwashed) denim, so shrinkage is discussed here in more detail than in most places.
| Item | Detail |
|---|---|
| Pre-shrunk (Sanforized) | Most jeans sold in shops. Shrinkage in the wash 1–3% (1–2 cm on an 80 cm waist) |
| Not pre-shrunk (raw denim, "shrink-to-fit") | Shrinks 5–10% in the first wash (3–8 cm at the waist and in length). Buying a larger size to allow for shrinkage is the assumption |
| Inch sizes | Waist W28–W36 etc. = about 71–91 cm. But a brand's actual measurement is normally the inch size plus 2–5 cm ("bigger than the label") |
| Stretching | Stretch 1–3 cm with wear (cotton stretches and does not recover well). Stretch blends (1–3% polyurethane/elastane) stretch even more |
| Tumble dryer | High heat causes heavy shrinkage and degrades stretch fabric |
| Japanese denim regions | Ibara and Kurashiki (Kojima) in Okayama Prefecture, Fukuyama in Hiroshima Prefecture — most of Japan's denim fabric. Known for selvedge denim (赤耳, "red ear") |
[Verify] Shrinkage rates are general figures from the textile industry and denim makers. Check the regional information against industry publications from Okayama and Hiroshima Prefectures.
Pre-shrunk jeans shrink 1–3%, which wear recovers. Raw denim shrinks 5–10%, which you allow for when buying. Check the tag and the brand's description.
An actual measurement 2–5 cm larger than the inch size is normal, and it differs by brand. Lay a pair you own flat, measure the waist and double it (×2), then compare in centimetres.
Cotton stretches 1–3 cm with wear and does not recover well. "Slightly tight breaks in within a few days" is the denim convention. Stretch blends stretch easily and recover easily.
The dryer makes shrinkage worse. Wearing them damp, or pulling them into shape as they dry, can recover a few centimetres (raw denim shrinkage does not come back).
It is a difference in how the fabric was finished: selvedge raw denim is often not pre-shrunk, so it shrinks. Sanforized Japanese denim behaves like any other. A "one-wash" (ワンウォッシュ) label means the jeans have already been washed once and shrunk.
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https://www.caa.go.jp/policies/policy/representation/household_goods/guide/fiber/
https://www.jisc.go.jp/
https://www.pref.okayama.jp/
⚠️ Editorial note: the source URLs above were identified by search. Our working environment cannot reach go.jp domains, so the contents have not been checked against the text. Verify every source before publication and record who checked it and when.
What we share here are ideas and everyday practices passed down among people living in Japan, together with general information drawn from public sources. They are not official recommendations, and they are not professional instruction. Practices vary between households and regions.
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