Why the label lets you down
A medium at one shop is a large at another, and a single brand can cut its own medium three ways in a season: regular, relaxed, boxy. The letter tells you which bracket the maker aimed at, not how the piece will sit on you.
What does not change is the cloth itself. A shirt measures the same across the chest whoever made it. So the reliable way to buy is to compare the new piece, number by number, with one you already know fits.
Measure one piece that fits
Pick the piece you reach for because of how it sits, not because you like the colour. Lay it flat on a table, smooth it out without stretching, and measure with a soft tape.
| Garment | Measure this |
|---|---|
| T-shirts, shirts, knitwear | Pit to pit (chest), back length from collar seam to hem, shoulder seam to seam, sleeve from shoulder seam to cuff |
| Jackets and coats | As above, plus the length you like over your trousers |
| Trousers and jeans | Waist straight across, inseam from crotch seam to hem, front rise, leg opening at the hem |
Write the numbers down with the brand and size on the label. Two or three pieces measured this way cover most of what you will ever buy.
Read the size guide the right way
Shop size guides come in two kinds, and mixing them up is the commonest mistake.
- Garment measurements are the piece itself, laid flat. Compare them directly with your own numbers. A chest given as a full circumference is double the pit-to-pit figure.
- Body measurements describe the person the size is meant for. They leave out the ease, the extra room the cut adds, so they say little about a relaxed or boxy piece.
If a page gives only body measurements, look for a line on the cut (oversized, regular, slim) and a model's height and size. Failing that, product reviews that mention fit are worth more than the chart.
What the numbers tell you
Within about 2 cm of your reference on chest and length, the piece will feel familiar. More than that is a choice, not an accident:
- 4 cm or more extra across the chest reads as deliberately relaxed. Good if that is the shape you want, too much if your reference is already loose.
- Shoulders matter more than chest. A seam that drops a little is fine on a relaxed piece; one that sits far down the arm makes the whole garment look borrowed.
- On trousers, rise and leg opening change the shape more than the waist. Match the rise you like and the rest follows.
Buy less, return less
Most returns are size returns. Ten minutes with a tape measure saves a parcel each way, and the habit of checking first tends to make you buy fewer, better pieces.