Sizing explained
What the words on a size chart mean: true to size, ease, garment measurements, petite, plus, sister sizes.
- What "true to size" means, and how to show itTrue to size means an item fits the way its size chart says, so shoppers take the size the chart gives them. A store shows it best on a fixed scale from runs small to runs large, with one line of fit note.6 min
- What vanity sizing is, and what a store can do about itVanity sizing is labeling clothes with a smaller size than their measurements would earn, so the number flatters. A store can't fix labels across an industry, but it can publish the measurements behind its own.5 min
- Body measurements vs garment measurementsA body measurement is the person; a garment measurement is the product, often laid flat and halved. The gap between the two is ease, and comparing one with the other is the quickest way to a wrong size.6 min
- How much ease clothes need: the numbers by garmentEase is the garment measurement minus the body measurement. A fitted top needs about 8.9 cm (3.5 in) at the chest, a regular one 11.6 cm (4.6 in), a regular coat 18.9 cm (7.4 in). The full table by garment is below.7 min
- Petite, tall, plus size, big and tall: what each meansPetite and tall are about length: the same widths, cut shorter or longer. Plus size and big are about girth: a larger chest, waist and hips. Big and tall is both at once.6 min
- Bra sister sizes explainedSister sizes hold the same cup volume on a different band. Go one band down and one cup up, or one band up and one cup down: the sisters of a 34C are 32D and 36B.5 min
- Size chart vs size guide: what's the differenceA size chart is the table: sizes on one side, measurements on the other. A size guide is everything a shopper needs to use it: the chart, how to measure, how the item fits, and a way to get a size from their own numbers.5 min
- Why a medium isn't the same size at every brandA medium is a name, not a measurement. Each brand decides which body its M fits, how much room it leaves and how sizes step up, so the fix is to publish the measurements behind your M and a one-line fit note.5 min
- Junior, youth and women's sizes: what's the differenceYouth sizes are children's sizes, chosen by height and age. Junior sizes, in odd numbers like 3, 5 and 7, are cut for teens and young women with a straighter shape. Women's sizes, in even numbers like 4, 6 and 8, are cut for an adult figure.6 min
- What "one size" means, and when it fitsOne size means the maker cut a single size to cover a range of bodies, through stretch, an adjustment or a loose cut. It fits when your body falls inside that range, so a one-size product should still say, in numbers, which bodies it fits.5 min
- How size grading works: from one sample to a size rangeGrading turns one approved sample into a full range of sizes. Every point of the pattern moves by a set amount per size, the grade rule. Girths grow by several centimeters a size, lengths by one or two, and the steps often widen toward the larger sizes.6 min
- Tolerance: why a garment can measure 1 cm off the chartTolerance is how far a finished garment may measure from its spec and still pass. Fabric, cutting, sewing and the tape itself all move the numbers a little, so a chart value is a target, not a promise to the millimeter. Keep the tolerance under half the step between sizes.6 min
- Maternity sizes: why you keep your usual sizeMaternity clothes use your pre-pregnancy size: if you wore a medium before, you take a maternity medium. The room for the bump is built into the cut and the fabric. Bras are the exception: measure again, because band and cup both change.5 min
- Activewear and compression sizing: tight on purposeActivewear and compression garments are made smaller than the body, so they hold. Size them by the brand's chart, not your usual letter, and follow the fit note: Ruban Size's templates say size up for comfort on leggings and cycling kit, size down for support on sports bras.6 min
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