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\nA birthday crew can need four size systems at once: months for the baby, T sizes for the toddler, youth letters for the big kids and adult letters for everyone else. This guide explains each one in plain words, so the birthday kid, the siblings and the grown-ups all end up in the right shirt. It also answers the question gift buyers ask most: 24M or 2T? If you are still unsure after reading, email support@teecrate.shop with the ages and usual sizes, and we will help.
\nNot every design comes in every size. A design made for a 3rd birthday comes in sizes a three-year-old and a few friends are likely to wear, and a design for a 10th birthday starts at youth sizes. Each product page shows only the sizes that style is made in, as buttons you can tap. Here is the general pattern:
\n| Product group | \nSize system | \nExamples | \n
|---|---|---|
| Baby bodysuits and baby raglan | \nBaby months: 6M to 24M | \nOne Candle First Birthday Baby Bodysuit, Cake Smash Name Baby Bodysuit | \n
| Birthday kid tees | \nToddler 2T to 5T and youth YXS to YXL, depending on the design | \nNumber Candle Birthday Kid Tee, Three Scoops 3rd Birthday Tee | \n
| Sibling and cousin tees | \nToddler and youth | \nSibling of the Birthday Kid Tee, Party Guest Crew Kids Tee | \n
| Youth tank top | \nYouth YXS to YXL | \nLucky Seven 7th Birthday Youth Tank Top | \n
| Grown-up tees and sweatshirt | \nAdult S to 5XL | \nBirthday Crew Role Tee, Birthday Crew Crewneck Sweatshirt | \n
| Tote | \nOne size | \nGoody Bag Canvas Tote | \n
Baby sizes are named by age in months. They are cut for babies in diapers, with room in the seat for a diaper.
\n| Size label | \nUsually chosen for | \nTypical birthday moment | \n
|---|---|---|
| 6M | \nBabies around six months | \nHalf birthday photos | \n
| 12M | \nBabies around their first birthday | \nFirst birthday party, cake smash | \n
| 18M | \nBigger one-year-olds, or a first birthday with room to grow | \nFirst birthday when the baby is tall for their age | \n
| 24M | \nBabies close to two, still in diapers | \nA second birthday for a child still in diapers | \n
Age in months is a starting point, not a rule. Babies grow at very different speeds, so look at the size your baby wears right now in other clothes. If those clothes are getting snug, choose the next size up.
\n24M is cut for a baby who is still in diapers, with more room in the seat, while 2T is a toddler cut that is a little longer and slimmer for a child who is walking and often out of diapers.
\nBoth labels are for children around two years old, which is why the question comes up so often. Here is how to choose:
\nOur baby bodysuits run up to 24M, and our toddler tees start at 2T, so a second birthday can go either way depending on the child.
\nT sizes are for toddlers who are on their feet and on the move. The number roughly matches the age, so 3T is a common pick for a third birthday. Toddlers who are big for their age, or kids who like a looser shirt, often wear one size up.
\n| Size label | \nUsually chosen for | \nTypical birthday | \n
|---|---|---|
| 2T | \nToddlers around two | \n2nd birthday | \n
| 3T | \nToddlers around three | \n3rd birthday | \n
| 4T | \nKids around four | \n4th birthday | \n
| 5T | \nKids around five, still in toddler sizes | \n5th birthday | \n
Around age four or five, many kids move from T sizes to youth sizes. If the birthday kid already wears youth XS in other clothes, pick youth XS here too.
\nYouth sizes are for school-age kids. They use letters instead of ages, and every brand cuts them a little differently, so the size your child wears in their school tees is the best guide.
\n| Size label | \nName | \nUsually chosen for | \n
|---|---|---|
| YXS | \nYouth extra small | \nKids moving up from 5T | \n
| YS | \nYouth small | \nYounger school-age kids | \n
| YM | \nYouth medium | \nKids in the middle of primary school | \n
| YL | \nYouth large | \nOlder kids | \n
| YXL | \nYouth extra large | \nThe tallest kids before adult sizes | \n
Ten-year-olds and their big siblings can land anywhere from youth medium to youth extra large. When in doubt, ask what they wear for sports or school.
\nEvery grown-up shirt in the store comes in exactly eight sizes: S, M, L, XL, 2XL, 3XL, 4XL and 5XL. That way the whole crew can wear the same design, from the smallest aunt to the biggest uncle.
\n| Size label | \nPrice | \nHow to choose | \n
|---|---|---|
| S, M, L, XL | \nBase price | \nPick the size the person wears in a regular everyday tee. | \n
| 2XL, 3XL | \nBase price +$2 | \nSame rule: the size they wear in an everyday tee. | \n
| 4XL, 5XL | \nBase price +$4 | \nSame rule: the size they wear in an everyday tee. | \n
The extra charge for bigger sizes is shown as soon as you choose the size, before anything goes into the crate.
\nEach style is cut a little differently, and we do not want to give you a number that does not match the shirt you receive. That is why this guide uses size labels instead of a measurement chart. If you need a measurement for a specific style before ordering, such as the chest width of the crewneck sweatshirt, email us with the product name and we will tell you what we have for that style.
\nIf you want to compare at home, lay a shirt that fits well flat on a table and measure straight across the chest, just under the arms, and from the top of the shoulder to the bottom hem. Keep those numbers with your email to us, and we can compare them for you.
\nGrandparents, aunts, uncles and godparents order a lot of our shirts, often without knowing the size system. A few tips:
\nHere is how one imaginary family might size a crate for a 4th birthday party. The birthday kid wears 4T in most clothes, so the Four-Alarm 4th Birthday Tee goes in at 4T. Because the party is two months away and he is growing fast, his parents choose 5T instead, so it still fits on the day. His big sister is eight and wears youth medium at school, so the Sibling of the Birthday Kid Tee goes in at YM. The cousin is six and wears 5T in most clothes but is ready for youth sizes, so the Party Guest Crew Kids Tee goes in at YXS, the size between the two that her parents say fits her best right now.
\nFor the grown-ups, Mama wears M in everyday tees, Dad wears 2XL and Grandpa wears 4XL. They each get the Birthday Crew Role Tee with “Birthday Boy” wording in their own size, and the price for Dad’s 2XL shows $2 extra while Grandpa’s 4XL shows $4 extra. In the crate, every one of those shirts is a separate line with its size written next to it, so the family can check each person once more before checking out.
\nThe lesson from the example: size each person in their own system, think about growth for the kids, and use the everyday tee size for the adults.
\nBirthdays happen all year, and the weather on party day changes what feels comfortable.
\nEach product page lists the sizes that style comes in, so check there before you plan matching outfits across different styles.
\nOn the Name & Age Birthday Kid Tee, the Cake Smash Name Baby Bodysuit and the Sibling Name & Role Kids Tee, the name is printed in the same layout on every size. On smaller sizes, a long name takes up more of the shirt’s width than on bigger sizes. The live preview on the product page shows the layout so you can see how a long name looks. Personalised shirts can be exchanged for a different size within 60 days of delivery like everything else; the new shirt is printed with the same name unless you tell us otherwise.
\nEvery item can be returned or exchanged within 60 days of delivery, for any reason, including personalised shirts. Email us with your order number, the shirt and the size you need, and we send you a free return label. An exchange shirt is prepared and shipped like a new order, so it takes 1-3 business days to prepare and 7-14 business days in transit. If the party is close, try on every shirt as soon as the parcel arrives. Full details are on the Returns & Exchanges Policy page.
\nReady to choose? Browse Birthday Kid Tees, First Birthday & Baby, Grown-Up Crew Tees and Siblings & Cousins. For timing, read Shipping & Delivery. For quick answers, see the FAQs, or email support@teecrate.shop; we reply within 24 hours on business days.
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