What is the difference between a youth 4 and a 4T in childrens clothes?

Answers:   The 'T' designates toddler sized. The toddler sizes are supposed to roughly represent that age group. i.e. a 2T should fit an average 2 year old on up to a 5T should fit an average 5 year old. Also, (as a previous answerer indicated) the toddler sizes are made bigger in the bottom to accommodate diapers. So a 5T is more convenient for a parent of a 5 year old boy or girl who still wears diapers. At that age the youth sizes have started, but are not as accommodating for diapers. The small youth sizes are just a little bit bigger than the biggest 'T' sizes. The youth sizes also don't have anything to do with age. It just might happen that your 5 year old wheres a youth 5, but that won't always be the case as they age.
This always confused me- but 4t is just a little smaller that youth 4- some stores it's hard to tell the difference.
4T clothes are nearing the end of the toddler sizes and size 4 is the smallest size in big boys clothes. Once children get into 5T, they can usually wear either size...5T or 4 in big boys. I am going through that phase now...still young enough to want sponge bob / spiderman...on everything they wear, but once you get to the bigger sizes there are more choices and better ones for special occasions.
Generally children's clothing that is designated with the T are bigger in the bottom to accommodate a diaper.

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