Underwear size table
Convert height and net waist into a Chinese trouser size code and men's or women's underwear letter size, with inch and chi conversions plus a fit allowance tip.
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Size result
Size code, letter size and inch/chi conversions.
Enter height and net waist to look up the size
Height band: 0 · Net waist: 0 · Inches: 0 · Chi: 0
What this tool does
- Measure your waist before ordering underwear online and get both the size code and the letter size instead of guessing from trouser size.
- Shop overseas: 80 cm converts to 31.5 inches, which lines up with W-based sizing.
- Order for family members from height and waist without asking 'what size do you wear'.
- Sanity-check your hip-to-waist drop: enter the hip measurement and the tool flags a possibly misplaced tape.
Example
Input
170,80,95
Output
号型：170/80A（下装以腰围为型，A = 标准体型） 净腰围 80 cm → 字母码 L 腰围换算：80 cm = 31.5 英寸 = 2.4 市尺 身高档：170 cm（号按 5 cm 分档） 选码建议：内裤比外裤贴身，腰围落在档位边界时取大一档更舒适（约留 2–4 cm 余量）。 各品牌版型差异较大，弹性面料与纯棉款的同码松紧度可以差一档。 臀围 95 cm，臀腰差 15 cm（正常范围）
For trousers the size code uses the net waist in cm; 1 inch = 2.54 cm and 1 chi = 33.3333 cm.
Frequently asked questions
Why is underwear sized by waist rather than height?
Under GB/T 1335 the trouser size code uses the net waist as the primary dimension and height as the secondary one, written like 170/80A. Underwear fit depends almost entirely on waist and hip, so height only forms the code while the letter size follows the waist bands.
How are the letter bands defined?
Common waist bands: men M 68–76, L 76–84, XL 84–92, 2XL 92–100, 3XL 100–110 cm; women S 58–64, M 64–70, L 70–76, XL 76–84, 2XL 84–92 cm. Brands vary by roughly one step.
What if my waist sits exactly on a band boundary?
Underwear sits closer than outerwear, so take the larger band and leave 2–4 cm of ease. The tool repeats this in the notes; stretchy fabrics can be sized down instead.
How are inches and chi converted?
1 inch = 2.54 cm (the international inch) and 1 chi = 1/3 m = 33.3333 cm. So 80 cm is 80 ÷ 2.54 ≈ 31.5 inches and 80 ÷ 33.3333 ≈ 2.4 chi.
What does the hip measurement do?
It produces the hip-to-waist drop with a short verdict. If the hip is not larger than the waist the measurement must be misplaced, so the tool reports an error instead of a misleading size.
Is the data uploaded?
No, everything is computed locally in the browser.
Keywords：内裤尺码underwear size腰围换算号型GB/T 1335尺码对照英寸换算