Independent guide · Not affiliated with LoongBuy
Unofficial guide
Measurements before letters
An S, M, L or printed shoe size is not a universal physical measurement. Cut, intended fit, measurement method and sizing system can all change what the label means. Begin with centimetres, then use the label as a final cross-check.
Measure a similar item that already fits the way you want. Body measurements are useful, but a reference garment also captures ease, layering and personal preference.
Use simple tools and one unit
- Flexible tape for body or curved measurements
- Rigid ruler or tape for flat garments and insoles
- A similar reference item that fits correctly
- Notes showing where every measurement was taken
- Centimetres as the comparison unit to reduce conversion confusion
If a chart uses inches, multiply the value by 2.54 to convert it to centimetres. Keep both values in your notes and avoid rounding until the final comparison.
Match the measuring method
Lay the reference item flat without stretching it. Measure between clear construction points and record whether a width is a flat half-measurement or a full circumference. A chest width of 58 cm measured pit to pit is not the same as a 58 cm chest circumference.
- Choose the same product typeCompare hoodie with hoodie, boot with boot and puffer with a similarly shaped outer layer.
- Use the same pointsMatch shoulder seam, armpit, hem, inseam or insole endpoints as closely as possible.
- Repeat the measurementA second pass catches a twisted tape or wrong endpoint.
- Record desired differenceNote whether you want the new item wider, shorter, more fitted or suitable for extra layers.
Measurements that matter by category
| Category | Start with | Important context |
|---|---|---|
| Sneakers | Foot length, insole or internal length | Confirm EU, US or UK system and allow for toe shape |
| Boots | Foot length, internal length, shaft opening | Include sock thickness and calf room where relevant |
| Hoodies | Chest width, body length, shoulder, sleeve | Dropped shoulders change how sleeve length is interpreted |
| Down jackets | Chest, shoulder, sleeve, back length | Measure over the layers you expect to wear |
| Coats | Chest, shoulder, sleeve, total length | Check closure room and intended silhouette |
| Jeans | Waist, rise, thigh, inseam, hem | Confirm whether fabric stretch is stated and how waist was measured |
| Headwear | Head circumference or internal opening | One-size labels still have a physical range |
| Bags | Width, height, depth, strap length | Use internal dimensions for fitted contents such as laptops |
Read proportions as a system
Do not choose clothing from chest width alone. Shoulder, sleeve, body length and hem shape work together. A wide chest with a short body creates a boxy fit; a dropped shoulder changes where the sleeve begins; a ribbed hem can gather a hoodie even when the flat width looks generous.
Chest width, shoulder width, sleeve length and back length establish the main silhouette.
Add layering space, closure room, hood shape and cuff or hem adjustment.
Waist alone is insufficient; rise, thigh, inseam and hem determine the complete fit.
Stretch and recovery matter, but images and measurements cannot predict them completely.
Separate printed size from internal space
Measure the foot at the end of the day and compare with a well-fitting insole when possible. Confirm whether the listing supplies foot length, insole length, internal length or outsole length—these numbers are not interchangeable. Width, toe shape and sock thickness also influence fit.
Pair sizing evidence with the sneaker QC workflowThe correct number still needs the correct use
Ease is the space between the body and garment. A close T-shirt, oversized hoodie and winter puffer require different ease even for the same person. Compare the new item with a reference that serves the same purpose, including the layers or socks you expect to wear.
Decide what difference is acceptable before seeing the result
Measurements are not perfectly exact. Soft fabric, tape tension, item position and the chosen endpoints can produce small differences. Set a personal tolerance for each critical dimension before comparing candidates, and use a second measurement when the result sits near your limit.
| Conflict | What it may mean | What to do |
|---|---|---|
| Chart and warehouse measurement differ | Different endpoints, production variation or an incorrect chart | Request a photo showing the tape and both endpoints |
| Correct width but wrong length | The overall proportion does not match the reference | Do not let one matching number overrule the complete fit |
| Foot length fits but width is unknown | Length alone cannot predict toe or forefoot comfort | Compare model shape and request width evidence when possible |
| Two sizes both look possible | The decision depends on ease, layers and preference | Choose against the reference garment, not the label |
The acceptable difference depends on product type, fabric, cut and how close the fit needs to be. Avoid publishing one fixed tolerance as if it works for every category.
Four shortcuts that create sizing errors
- Choosing only by the familiar size letterThe same letter can represent different physical dimensions.
- Confusing garment width with body circumferenceCheck whether the chart is flat, doubled or based on body recommendations.
- Comparing different measurement pointsA sleeve measured from the collar cannot be matched directly to one measured from the shoulder seam.
- Ignoring intended useWinter socks, base layers, dropped shoulders and fitted compartments change the required room.
LoongBuy spreadsheet sizing FAQ
How do I choose a size from a LoongBuy spreadsheet?+
Measure a comparable item that already fits, then match the same measurement points to the current listing. Use the size label only after the centimetre measurements make sense.
Should I size up for LoongBuy clothing?+
There is no universal rule. Compare garment measurements, desired fit and layering needs. Sizing up automatically can create the wrong shoulder, sleeve or body proportions.
Are seller size charts reliable?+
Treat a chart as evidence to verify rather than a guarantee. Confirm whether it shows garment or body measurements, check the unit, and request flat measurements when the decision is close.
How much extra room should a winter jacket have?+
It depends on the intended layers and cut. Measure a jacket that already works over your normal winter layers and use that garment as the comparison reference.
How do I convert inches to centimetres?+
Multiply inches by 2.54. Keep the original unit alongside the conversion so you can catch typing or rounding mistakes.
Can QC photos replace measurements?+
No. Photos help with shape and proportions, but perspective and styling can mislead. Measurements are still required when fit matters.