Children's Briefs and Underwear Sizes

Children's underwear sizes follow height in cm or age. Main grids: 86-92 (2-3 years), 98-104 (3-4y), 110-116 (5-6y), 122-128 (7-8y), 134-140 (9-10y), 146-152 (11-12y), 158-164 (13-14y). Underwear should fit snug without compressing.

Unlike outerwear, underwear should not be bought too large 'for growth': loose briefs bother, slip and don't provide the expected hygiene function. Buy the exact size and replace every 6-8 months as the child grows.

Average age5/678910
Height / Stature105-116117-122123-128129-134135-140
Chest circumference in cm6062646768
Waist circumference in cm5455565759
Hip circumference in cm6264666971
Size to order114120126132138
Average age11/1213/1415/1617/18
Height / Stature141-152153-158159-164177-186
Chest circumference in cm75828892
Waist circumference in cm63667176
Hip circumference in cm78849296
Size to order150162174180

Frequently asked questions

How do I measure for underwear size?

Take child's height in cm and waist circumference. Height gives the base size; waist refines. A 122 cm child with 58 cm waist takes 122-128 cm. If slim or sturdy, adjust one size.

Difference between briefs, boxers and panties for kids?

Briefs cover hips and intimate area (classic cut). Boxers extend slightly onto thighs (short shorts style). Panties for girls have similar cut to briefs but often with patterns and softer fabric. All 3 use the same size grid.

Organic or regular cotton for children?

Organic cotton is recommended for sensitive skin (infants, atopic children). For a child without particular concern, quality regular cotton works well. Avoid pure synthetic fabrics which cause sweating and irritation.

How often to check underwear sizes?

Every 3-4 months before age 6, then every 6 months. Signs to change: red marks after wearing, elastic cutting in, fabric max-stretched. Too-small briefs can irritate skin without the child complaining.

Should I buy unisex or gendered briefs?

Before age 3-4, briefs are often unisex (same cuts). Beyond, boys' briefs have a front opening, girls' don't. Comfort is identical. Choice is aesthetic (patterns) and practical (opening for toilet use).

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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