Baby clothing sizes, by date and by brand
What size will baby wear on the big day?
Pick a date, pick the brands, and get the size that will fit when it counts. Built on 28 current brand size charts.
Start with a birth or due date
Sizes for each brand you pick will appear here, ready for the date you choose.
How it works
Three taps to the right size
The same tool you just saw, running on its own. It projects growth to your date, then reads each brand's published chart.
Demonstration: a birth date is entered, Christmas is chosen as the occasion, three brands are selected, and a size appears for each brand, with an option to add weight and length for a sharper answer. Then one brand's size is compared with another brand's sizes using overlapping bars.
Coming up
Shopping for an occasion?
Tap an event to load its date into the calculator, or see the answer for every birth month.
Halloween
October 31, 2026 in 21 days fall
Thanksgiving
November 26, 2026 in 47 days fall
Christmas
December 25, 2026 in about 2 months winter
New Year's Day
January 1, 2027 in about 3 months winter
Valentine's Day
February 14, 2027 in about 4 months winter
Easter
March 28, 2027 in about 6 months spring
Methodology
Real growth data, real size charts
Growth is projected with the World Health Organization Child Growth Standards. Sizes come from the chart each brand publishes, checked against the brand's own site, with the source and retrieval date listed on each brand page. Every result shows a likely size and an honest range.
- Private by design. No accounts and no tracking. What you type stays on your device.
- Brand by brand. A 6M is not the same everywhere. Each brand is read from its own chart.
- Season aware. Every result names the season, so the size and the sleeves both fit.