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Size Guide - Ralph Lauren
| APPROXIMATE AGE | BABY HEIGHT (IN) | BABY HEIGHT (CM) |
| NEWBORN | 21 | 53 |
| 3 MONTHS | 21-24 | 53-60 |
| 6 MONTHS | 24.5-27 | 62-68 |
| 9 MONTHS | 27.5-29 | 70-74 |
| 12 MONTHS | 29.5-31 | 75-79 |
| 18 MONTHS | 31.5-33 | 80-83 |
| 24 MONTHS | 33.5-35.5 | 85-90 |
| ONE SIZE (9 MONTHS - 24 MONTHS) | 27.5-35.5 | 70-90 |
| APPROXIMATE AGE | Junior Boys height (IN) | Junior Boys height (CM) |
| US 2 YEARS / UK 1.5 YEARS | 34.5-36.5 | 88-93 |
| US 3 YEARS / UK 2 YEARS | 37-39.5 | 94-100 |
| US 4 YEARS / UK 3 YEARS | 40-42.5 | 102-108 |
| US 5 YEARS / UK 4 YEARS | 43-45.5 | 109-116 |
| US 6 YEARS / UK 5 YEARS | 46-48.5 | 117-123 |
| US 7 YEARS / UK 6 YEARS | 49-53 | 124-134 |
| ONE SIZE (US 2-4 YEARS / UK 1.5-3 YEARS) | 34.5-42.5 | 80-108 |
| APPROXIMATE AGE | Junior Girls height (IN) | Junior Girls height (CM) |
| US 2 YEARS / UK 1.5-2 YEARS | 34.5-36.5 | 88-93 |
| US 3 YEARS / UK 3 YEARS | 37-39.5 | 90-100 |
| US 4 YEARS / UK 4 YEARS | 40-42.5 | 102-108 |
| US 5 YEARS / UK 5 YEARS | 43-45.5 | 109-116 |
| US 6 YEARS / UK 6 YEARS | 46-48.5 | 117-123 |
| US 6X YEARS / UK 6.5 YEARS | 49-50.5 | 124-128 |
| ONE SIZE (US 2-4 YEARS / UK 1.5-4 YEARS) | 34.5-42.5 | 80-108 |
| APPROXIMATE AGE | Boys height (IN) | Boys height (CM) |
| (S) US 8 YEARS / UK 6-7 YEARS | 53.5-54.5 | 136-138 |
| (M) US 10 YEARS / UK 8 YEARS | 55-56 | 140-142 |
| (M) US 12 YEARS / UK 9 YEARS | 56.5-58.5 | 144-149 |
| (L) US 14 YEARS / UK 10-12 YEARS | 59-61 | 150-155 |
| (L) US 16 YEARS / UK 12-14 YEARS | 61.5-63.5 | 156-161 |
| (XL) US 18 YEARS / UK 14 YEARS | 65-66 | 163-168 |
| (XL) US 20 YEARS / UK 16 YEARS | 66.5-68.5 | 169-174 |
| S/M (US 8-12 YEARS / UK 6-9 YEARS) | 53.5-56 | 136-149 |
| L/XL (US 14-20 YEARS / UK 10-16 YEARS) | 59-68.5 | 150-174 |
| APPROXIMATE AGE | Girls height (IN) | Girls height (CM) |
| US 7 YEARS / UK 7 YEARS | 51-53 | 130-134 |
| US 8 YEARS / UK 8 YEARS | 53.5-54.5 | 136-138 |
| US 10 YEARS / UK 9 YEARS | 55-56 | 140-142 |
| US 12 YEARS / UK 10 YEARS | 56.5-58 | 144-147 |
| US 14 YEARS / UK 11 YEARS | 58.5-60.5 | 149-154 |
| US 16 YEARS / UK 12-14 YEARS | 61-62.5 | 155-159 |
| S/M ( US 7-10 YEARS / UK 7-9 YEARS) | 51-56 | 130-142 |
| L/XL ( US 12-16 YEARS / UK 10-14 YEARS) | 56.5-62.5 | 144-159 |
HOW TO MEASURE
HEIGHT
Measure under your arms at the fullest part of your bust. Keep the tape level.
CHESTMeasure the total circumference with the tape placed horizontally around the largest part of the chest.
HIPSStand with your feet together and measure around the fullest part of your hips.
Baby Boys Navy Short Sleeve Romper
£50.00