| O'Neill product size | US size | EU size | UK size | Waist (cm) | Hip (cm) |
| XS | 1 | 32/34 | XS | 60-64 | 86-90 |
| S | 5 | 34/36 | S | 65-69 | 91-95 |
| M | 7 | 38 | M | 70-74 | 96-100 |
| L | 11 | 40/42 | L | 75-79 | 101-105 |
| XL | 13 | 42/44 | XL | 80-84 | 106-110 |
Chest:With you arms relaxed by your side, measure around the fullest part of you chest
Waist:Measure around your natural waistline.
| O'Neill product size (EU/UK) | Pant size (inches) | Waist (cm) | Hip (cm) |
| XS | 28-29 | 72-77 | 87-91 |
| S | 30-31 | 78-82 | 92-96 |
| M | 32-33 | 83-87 | 97-101 |
| L | 34 | 88-93 | 102-106 |
| XL | 36 | 94-99 | 107-112 |
| XXL | 38 | 100-105 | 113-118 |
Waist:Measure around your natural waistline.
Hips:Measure around the fullest part at the top of your hips.
Inseam:Using pants that fit well, measure from the crotch seam to the bottom of the leg.
| Age | Product size (EU) | Chest size (cm) | Waist size (cm) | Hip size (cm) |
| 1.5-2 | 92 | 54 | 49 | 54 |
| 2-3 | 98 | 55 | 50 | 56 |
| 3-4 | 104 | 56 | 51 | 58 |
| 5-6 | 116 | 58 | 53 | 62 |
| 7-8 | 128 | 62 | 56 | 66 |
| 9-10 | 140 | 66 | 59 | 70 |
| 11-12 | 152 | 72 | 64 | 76 |
| 13-14 | 164 | 78 | 69 | 82 |
| 14-15 | 176 | 84 | 74 | 88 |
Chest:With you arms relaxed by your side, measure around the fullest part of you chest
Waist:Measure around your natural waistline.
Hips:Measure around the fullest part at the top of your hips.
Inseam:Using pants that fit well, measure from the crotch seam to the bottom of the leg.