Why clothing is the hardest category
Anyone buying oopbuy clothes for the first time discovers the same thing: the photo shows a garment on a model who is not you, in lighting that is not your room, at an angle chosen to flatter. None of that tells you whether the chest is 58 cm or 62 cm, whether the fabric is 180 gsm or 320, or whether the shoulder seam will sit where you want it.
None of it is unsolvable either. Four flat measurements, one fabric number and a QC photo checklist will get you most of the way there. This guide is the overview; the individual guides on this site go deeper by garment type.
Measurements before anything else
Lay a garment you already own flat on a table and measure it. Do this for one top, one bottom and one jacket, and write the numbers down. From then on, you can read any size chart in about fifteen seconds.
| Measurement | Where to measure | Typical use |
|---|---|---|
| Chest width | Armpit to armpit, flat | Primary fit decision |
| Body length | Shoulder point to hem | Cropped vs regular vs long |
| Sleeve | Shoulder seam to cuff | Wrist coverage |
| Shoulder | Seam to seam, back | Structure and oversize feel |
| Waist | Across the waistband, doubled | Bottoms |
| Inseam | Crotch seam to hem | Trouser length |
Compare your numbers with the chart, not with the label. A chart that says "L: chest 120 cm" is telling you the full circumference; halve it to compare with your flat measurement. Confusing the two is the single most common sizing error in this market.
Reading a Chinese size chart
Most charts list 胸围 (chest), 衣长 (length), 袖长 (sleeve), 肩宽 (shoulder), 腰围 (waist) and 裤长 (trouser length). Some use half-measurements, some full. Look for a unit note — almost always centimetres — and for whether the number is "around" or "across".
If the chest figure is roughly double the flat width you would expect, it is a circumference. If it is close to your flat measurement, it is a flat width. Charts are usually consistent within a listing but not between listings, so never carry a number from one product to another.
Fabric weight: the number that predicts everything
Fabric weight in gsm is the best proxy for how a garment will feel and behave. It determines warmth, opacity, drape and how the piece survives washing.
- 140–180 gsm: thin jersey. Summer tees, base layers. Can be slightly transparent in white.
- 180–220 gsm: standard cotton tee. The everyday middle.
- 220–260 gsm: heavyweight tee. Holds its shape, less cling, warmer.
- 280–350 gsm: sweatshirt fleece. Light outer layer.
- 400+ gsm: heavy fleece. Structured hoodies and winter pieces.
These ranges are typical rather than standardised. Sellers measure differently and some quote the fabric before washing, so treat them as orientation. If a listing does not state a weight, the inside of the garment photographed close up is the next best clue: visible loops mean fleece, a smooth knit means jersey.
Fit language, translated
Listings use a small vocabulary loosely. It helps to know roughly what each term implies:
- Regular fit — follows the body with a little ease. The safest default.
- Boxy — wide through the chest, often shorter in the body. Buy your measured size unless you want extra width.
- Oversized — deliberately large throughout, including the sleeve and shoulder.
- Slim fit — close through the chest and waist. Check the chart carefully; slim cuts punish a wrong guess.
- Drop shoulder — the seam sits off the shoulder, so the sleeve measures longer than it looks.
When a listing says "oversized", compare its chest width with your own measurement plus 8–12 cm. If it is only 4 cm wider, it is boxy rather than oversized, and you may want to size up.
A wardrobe, not a shopping cart
The most expensive clothing mistakes are not bad garments; they are good garments that do not combine. Before ordering, sketch three outfits using only the items in your cart. If an item appears in none of them, it is a purchase waiting to be regretted.
- Choose two neutrals — black, grey, navy, ecru, olive.
- Add one accent that works with both neutrals.
- Check silhouette variety — one relaxed top, one fitted bottom, or the reverse.
- Cover the layers — base, mid, outer. See the jacket guide for outerwear sizing.
QC for clothing: what to look at
When your items reach the warehouse, photos are taken. Use them properly:
- Size label — matches what you ordered, and matches the chart.
- Flat shape — the body length and shoulder width look like the listing, not a different cut.
- Seams — straight, no puckering, no loose threads at stress points.
- Prints and embroidery — centred, straight, correctly placed.
- Colour — compare with the listing, allowing for warehouse lighting.
If you are unsure about fit, ask for a flat measurement of the chest and length. It is a small request and it settles the question before the parcel ships.
Care that makes a difference
Wash cold, inside out, with similar colours. Dry flat or on low heat; hanging a wet knit will stretch it. Heavy cotton may shrink slightly on the first hot wash, which is one reason to buy your measured size rather than sizing down. A garment at 260 gsm maintained properly will outlast three thin ones, and it will keep its shape at the collar and cuffs, which is where cheap clothing ages first.
Where to go next
Once the basics are clear, the individual guides cover the decisions that matter per category: hoodie weights and cuts, trouser and cargo fits, and the styling side for Y2K, vintage and distressed pieces.