PickGlobeChildren's clothing sizes are less reliable than adult sizes, because children grow quickly and the age on the label is only a rough guide. The most dependable way to buy a dress online is to measure your child and compare the numbers with the seller's own chart.
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Measure first
Use a soft tape measure while your child stands relaxed, in light clothes.
- Height: barefoot against a wall, from the floor to the top of the head.
- Chest: around the fullest part, under the arms.
- Waist: around the natural waist, above the navel.
- Dress length (if needed): from the base of the neck at the shoulder to the length you want. Compare it with the product's listed length.
Match height and chest first. Age labels can be off by a size or more.
How US and UK children's sizes differ
| US | UK | |
|---|---|---|
| Babies and toddlers | Months, then 2T, 3T, 4T | Months, then ages 2-3 years and so on |
| Children | Numbers such as 4, 5, 6, 6X, 7 | Ages such as 4-5 years, 6-7 years, or height in cm |
| Girls' larger sizes | Often S, M, L, XL, or numbers up to 16 | Ages up to 14 or 15, or height in cm |
Many UK and European brands label by height in centimetres, such as 116 cm, which is often more accurate than age. Many US brands label by number or letter. If a size chart gives both, use height.
Brands differ, so always use the chart for the brand you are buying from. Charts are usually a guide to a typical child's measurements, not a promise of fit.
How much growing room to allow
- A little extra is usually better than a lot. A dress that is too big can look and feel awkward, and the hem and sleeves can catch.
- Look for adjustable features such as buttons at the shoulders, ties, elastic waists and deep hems that can be let down.
- If between sizes, check the product description for fit: "runs small" or "generous fit" from the seller is useful. Consider the occasion: a party dress that needs to fit well suits the closer size, while everyday dresses can be roomier.
Fabric and comfort
| Fabric | Good to know |
|---|---|
| Cotton and cotton blends | Breathable, easy to wash, often the most comfortable for everyday wear |
| Knit and jersey | Stretchy, forgiving on fit and easy to move in |
| Corduroy and wool blends | Warmer, can need more careful washing |
| Polyester and synthetic blends | Quick drying and wrinkle resistant, but less breathable |
| Lined or tulle party dresses | Check for scratchy seams or labels, and whether the lining is soft |
Check the care label before buying: machine washable fabrics save time. Our guide to understanding fabric labels explains the terms.
Safety details to check
- Cords and drawstrings. Rules in the US and UK restrict some cords and drawstrings on children's clothing, especially near the neck and hood. If a dress has ties or cords, check where they sit and how long they are.
- Small parts. Buttons, bows and decorations should be firmly attached, especially for toddlers.
- Nightwear and flammability. Children's nightwear is subject to separate flammability rules in many countries. If you are buying pyjamas or nightdresses, look for the seller's statement that they meet the rules where you live.
- Labels and fibre content. Reputable sellers list the fabric composition, so a missing label is a reason to ask.
Our guide to toy age ratings and safety marks covers similar checks for toys.
Matching outfits
Some brands sell matching styles for mothers and daughters. If you are ordering a pair, check that both sizes come from the same size chart and that both items are in stock before you order, because colours and prints can sell out in one size.
Returns and exchanges
- Can you exchange for another size if it doesn't fit, and who pays postage?
- How long is the return window, and do items need to be unworn with tags attached?
- Are sale items excluded?
If you are ordering from abroad, check import charges and delivery times, as explained in our international shipping guide. If something goes wrong, see refunds and chargebacks. Our guide to reading clothing size charts explains how to compare charts.
The short version
Measure your child's height, chest and waist, use the seller's size chart rather than the age label, allow only a little growing room, and choose comfortable, washable fabrics. Check cords, small parts and nightwear rules, and read the exchange terms before you order.