Child size calculator

Estimate the clothing size for a child based on their age or height.

Children's sizes are defined by height (in cm) rather than age, because children grow at very different rates. An 8-year-old can be 120 cm or 130 cm — clothing size follows the measurement, not the birth year. Age remains a useful reference when shopping without being able to measure.

Our table covers all the correspondences between age, height in cm, and clothing size (from birth to 16 years). For growing children, size up when at the limit. For winter clothes (warm, lasting), one size up lets them wear it longer.

How to measure your child
  1. Have the child stand against a wall, barefoot, heels against the wall.
  2. Head straight, looking horizontally.
  3. Place a book on top of the head, perpendicular to the wall.
  4. Mark the book's position on the wall and measure the height in cm.
Child's ageHeight (cm)FR size
0-3 mois45-6056
3-6 mois61-6762
6-9 mois68-7168
9-12 mois72-7974
18 mois80-8580
2 ans86-9186
3 ans92-9792
4 ans98-10398
5 ans104-109104
6 ans110-115110
7 ans116-121116
8 ans122-127122
9 ans128-133128
10 ans134-139134
11 ans140-145140
12 ans146-151146
13 ans152-157152
14 ans158-163158
16 ans164-170164

Frequently asked questions

Should I buy by age or by height (cm)?

Always by height in cm. Children's body shapes vary widely at the same age. Age is only a guide when buying gifts without measuring.

How do I shop for a fast-growing child?

Size up when at the limit (e.g. if the child is 115 cm, get the 6-year/110 cm if slim, the 8-year/116 cm if sturdy). For winter clothes worn one season only, size up.

Is there a difference between baby and child sizes?

Baby sizes go from 0-3 months (size 56) to 24 months (size 86). Beyond that, you enter children's sizes: 2 years (86), 3 years (92), etc. Transition happens around age 2.

Are US sizes (4T, 5T, etc.) equivalent?

Approximately: 4T = about 100-104 cm (FR 4 years), 5T = 104-110 cm (FR 5), 6T = 110-116 cm. Cuts may differ (often wider in US).

Quicksize is your reference guide for all clothing and shoe size conversions. Whether you are looking for equivalences for men, women or children, we help you find the perfect size for your online shopping internationally (US, UK, EU, IT, etc.).

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