Record measurements and sizes properly
A size is not a fact until you know what it measures and in which unit. Keeping your own numbers and the seller's numbers in separate, labelled columns turns a hopeful guess into a check you can repeat for the next item.
Start with your own numbers
Before a size chart can mean anything, you need your own measurements taken once, in good light, with a soft tape and no clothing bulk. Chest or bust, waist, hip, inside leg, and foot length in centimetres will cover most apparel and footwear decisions. Write them in a block at the top of the sheet and add the date you measured — bodies change and so should the record.
Do not convert your measurements into a brand's letter size and then compare letters. Compare numbers. Letters differ between labels; centimetres do not.
Body and garment are different
The most common sizing error is comparing a body measurement with a garment measurement. A 104 cm chest circumference on a chart is not the same as a 52 cm flat chest width on a coat, even though one is roughly half of the other. They are measured differently, on different things.
| Basis | What it measures | Typical use | Watch out for |
|---|---|---|---|
| Body | Around or along your own body | Size charts that say "to fit chest" | Ease is already allowed for, or not |
| Garment, flat | Item laid flat, pit to pit | Second-hand and resale listings | Double it before comparing with a body figure |
| Garment, circumference | All the way round the item | Detailed size tables | Fabric stretch is not included |
| Foot length | Heel to longest toe, in cm | Trainers and boots | UK labels vary between brands |
Units, tolerance and rounding
Record the unit in the cell or in the column header, never in your head. Mixing inches and centimetres in one column is how a 22 becomes ambiguous. If a seller publishes inches only, convert once and note both values, with a marker showing which was converted.
Allow a tolerance. A tape measure on soft fabric, a hand-held ruler on a shoe, and a factory chart are three different instruments, so treat anything within about 1–2 cm as effectively the same. State your tolerance in the sheet so future you does not agonise over a rounding difference.
One coat, worked through
Say your measured chest is 96 cm and you want a wool-blend coat that will layer over a jumper. A worked record might look like this — all figures invented for the example.
- Your chest: 96 cm, measured 12 October 2026.
- Seller's chart: UK 12 lists 98 cm "to fit chest" — a body measurement, so directly comparable.
- Garment flat width: 53 cm pit to pit, which is 106 cm around. That implies roughly 10 cm of ease over your body measurement.
- Layer check: a mid-weight jumper adds perhaps 1–2 cm of bulk. 10 cm of ease is usually workable, but sleeve length and shoulder width still need confirming.
- Status: size plausible, sleeve and shoulder unconfirmed — ask the seller, or drop the row from the budget until answered.
For footwear the same logic applies with different fields: foot length in cm, the seller's UK size, and any note about whether the last runs narrow or wide. A UK 7 in one trainer is not evidence about a UK 7 in another, so keep the brand and the chart date next to the number.
What stays unconfirmed
Some things a chart cannot tell you: how a fabric drapes, whether a shoulder is structured, how a sole flexes. Those go in a separate "needs confirmation" field, phrased as a question you could send to the seller. A question in a cell is honest. A guess in a cell is a future mistake with a date attached.
Once the size fields are settled, move to the visual check in reading inspection photos, or return to the full field list in comparing product details. If the item is for a specific season or trip, the fit question also belongs in adapting a list to the season. Otherwise go back to the hipobuy spreadsheet home page and price the shortlist.
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