Niche verticals May 11, 2027 4 min read
Size Guide for Children's Swimwear
Kids' swimwear sized by age band + height + weight. Rashguards essential for sun protection. Swim diapers required for non-toilet-trained at most pools.
The Chart
| Age | Boy Trunk | Girl Suit | Notes |
|---|---|---|---|
| 0-12M | NB-12M | NB-12M | Sun-protective UPF rated |
| 1-3 | 12M-3T | 12M-3T | Easy on/off |
| 4-6 | 4-6 | 4-6 | One-piece for girls common |
| 7-12 | 7-12 | 7-12 | More style choices, rash guards |
| 13+ | Adult sizing | Adult sizing | Adult swim brands |
FAQs
Swim diaper vs regular?
Pools require swim diapers (don't expand in water). Regular diapers swell + leak. Reusable swim diapers (Bumkins) eco-friendly. Disposable easier.
UPF rating?
UPF 50+ blocks 98% of UV rays. For kids in sun 1+ hour, UPF rashguard essential. Full-coverage swim option for high-sun areas.
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