Swimsuit Sizes: Complete Sizing Guide

Swimsuit sizes vary by gender and brand with measurements in inches and centimeters. This guide compares women's, men's, and kids sizes with conversion charts to help you find the perfect fit.

Women's Swimsuit Sizes

Women's swimsuit sizing is based on bust, waist, and hip measurements. Sizes run XS to 3XL.

Size Bust (in / cm) Waist (in / cm) Hip (in / cm)
XS (0-2) 32-33 / 81-84 24-25 / 61-64 34-35 / 86-89
S (4-6) 34-35 / 86-89 26-27 / 66-69 36-37 / 91-94
M (8-10) 36-37 / 91-94 28-29 / 71-74 38-39 / 97-99
L (12-14) 38-40 / 97-102 30-32 / 76-81 40-42 / 102-107
XL (16-18) 42-44 / 107-112 34-36 / 86-91 44-46 / 112-117
2XL (20-22) 46-48 / 117-122 38-40 / 97-102 48-50 / 122-127

Men's Swimwear Sizes

Men's swim trunks are sized by waist measurement. Board shorts and swim briefs use similar sizing.

Size Waist (in / cm) Hip (in / cm)
XS (28-30) 28-30 / 71-76 34-36 / 86-91
S (30-32) 30-32 / 76-81 36-38 / 91-97
M (32-34) 32-34 / 81-86 38-40 / 97-102
L (36-38) 36-38 / 91-97 42-44 / 107-112
XL (40-42) 40-42 / 102-107 46-48 / 117-122
2XL (44-46) 44-46 / 112-117 50-52 / 127-132

Kids Swimsuit Sizes

Kids swimwear is sized by age and height. Measurements vary by brand and growth rate.

Size Age Range Height (in / cm)
2T-3T 2 to 3 years 33-38 / 84-97
4T-5T 4 to 5 years 39-44 / 99-112
XS (6-7) 6 to 7 years 45-50 / 114-127
S (8-10) 8 to 10 years 51-56 / 130-142
M (10-12) 10 to 12 years 57-62 / 145-157
L (14-16) 14 to 16 years 63-66 / 160-168

Visual Size Comparison

Swimsuit size progression from XS to XL.

Swimsuit size comparison XS M XL 2XL

Swimsuit Size Calculator

Find your swimsuit size based on measurements.

How to size swimsuits correctly

Measure first, label second

Pick a tape measurement and match it to the chart. Labels (S/M/L, US/UK/EU numbers) drift between brands; the underlying body measurement does not. Bust, waist, and hip measurements over the underwear you'll wear. Suits should be tight when dry and relax in water.

Picking between two sizes

Pick the smaller of two sizes for one-piece and bikini tops; pick the larger for high-cut bottoms. Synthetic spandex blends loosen with chlorine and sun exposure.

Brand and regional variation

The same labeled size can differ by a full size between brands and regions. Asian brands generally run a half size smaller than US brands; European brands fall in between. When in doubt, use the centimetre or inch measurement on the size chart, never the letter.

Common mistakes

  • Sizing by your old favourite without checking the new brand's chart.
  • Skipping the measurement step. Body shape changes; old numbers go stale.
  • Picking too tight in non-stretch fabrics — they don't break in the way leather does.
  • Trusting a single review's "runs small / runs large" without looking at the reviewer's measurements.