A baby clothing size chart helps you find the right fit based on your child's actual measurements rather than guessing by age alone. Because sizing varies significantly between brands — Carter's runs large while H&M runs small — using weight and height gives you the most accurate size recommendation across all major baby clothing brands.
Baby's Measurements
Recommended Size
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Brand Size Comparison
Sizing varies by brand. This table shows the likely size your baby will wear at each brand.
| Brand | Likely Size | Sizing |
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Standard US Baby Clothing Sizes
| Size | Age | Weight (lbs) | Height (in) |
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Baby Shoe Size Reference
| Age | US Size | Foot Length (in) |
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How to Use the Baby Clothing Size Chart
Finding the right baby clothing size can be frustrating because sizing varies wildly between brands and does not always match your baby's actual age. A 6-month-old might wear 3-6M at one brand and 6-9M at another. This free baby clothing size chart takes the guesswork out by using your baby's weight and height to recommend the best size across all major brands.
Step 1: Enter Your Baby's Age
Select your baby's age range from the dropdown. This gives a starting point for the size recommendation, but the tool primarily relies on weight and height for accuracy. If you only know the age, the tool will still provide a general recommendation based on standard size charts.
Step 2: Choose Your Units
Toggle between imperial (pounds and inches) and metric (kilograms and centimeters) using the unit switcher. The tool converts all measurements automatically, so you can enter whichever units you are most comfortable with.
Step 3: Enter Weight and Height
Enter your baby's current weight and height. Weight is the most important measurement for baby clothing sizes because it determines how the garment fits around the torso and legs. Height helps narrow the recommendation further, especially for sleepers and one-piece outfits. If you do not know the exact height, you can leave it blank and the tool will use weight alone.
Step 4: Review the Results
After clicking Find Size, you will see your recommended standard US size along with a brand comparison table. The table shows what size your baby would likely wear at Carter's, Old Navy, Gap, H&M, Zara, Gerber, Cat & Jack, and Primary. Brands that run large will suggest a smaller size label, while brands that run small will suggest sizing up. If your baby falls between two sizes, the tool recommends sizing up for comfort and longevity.
Understanding Brand Differences
Baby clothing sizes are not standardized across brands. American brands like Carter's and Old Navy tend to run generous, meaning your baby may fit a smaller labeled size than expected. European brands like H&M and Zara use different sizing conventions and tend to run smaller for US shoppers. This baby clothing size chart accounts for these differences so you can shop confidently at any store without guessing. When in doubt, always size up — babies grow fast, and a slightly roomier outfit is always more practical than one that is too snug.
Frequently Asked Questions
Is this baby clothing size chart free?
Yes, this baby clothing size chart is completely free with no signup required. All calculations run locally in your browser, so you can use it as many times as you need without creating an account.
Is my baby's data private?
Absolutely. All calculations happen entirely in your web browser using client-side JavaScript. No data about your baby is ever sent to a server or stored anywhere. Your information stays on your device.
Should I use age, weight, or height to determine baby clothing size?
Weight is the most reliable indicator for baby clothing size because babies of the same age can vary significantly in size. Height is the second most useful measurement. Age-based sizing is a rough guide but less accurate since growth rates differ widely.
Why does my baby need a different size at different brands?
Baby clothing brands use different size standards. Some brands like Carter's and Old Navy run large, meaning your baby may fit a smaller labeled size. European brands like H&M and Zara tend to run small. This tool shows you the likely size at each brand based on your baby's measurements.
Should I size up or down if my baby is between sizes?
Always size up when your baby is between sizes. Babies grow quickly, so a slightly larger garment will last longer. A too-tight outfit is uncomfortable and may restrict movement. Most parents find it practical to buy one size ahead of their baby's current measurements.
How often should I check my baby's clothing size?
Babies grow rapidly, especially in the first year. Check sizing every 4-6 weeks for infants under 6 months, and every 2-3 months for older babies. Growth spurts can happen suddenly, so if clothes seem snug around the shoulders, legs, or belly, it is time to size up.
Are baby shoe sizes included in this tool?
Yes, the tool includes a shoe size reference section for babies and toddlers aged 6 months and older. Baby shoe sizing varies by brand, so the reference provides general US size ranges based on foot length and age.
Do European and US baby sizes differ?
Yes, European baby sizes are based on the baby's height in centimeters rather than age ranges. For example, EU size 68 fits a baby about 68 cm tall. US sizes use age-based labels like 3-6M. This tool helps you find the right size in both systems.