Recently, I have noticed that a lot of buyers and sellers are confused as to what the difference between a Juniors size is and a Girls or a Juniors size versus a Womens size (misses). Juniors sizing runs larger then Girls (7-16) sizing but smaller then Women's Sizing. A girls size 16 is NOT a Juniors size 16! And a Womens 10 is NOT a Juniors 10!

First of all, Girls sizes are marketed for young girls, usually pre-teens (usually size 7-16). Juniors are marketed for the teens and usually are styled for a body conscious fit, fitting tighter around the curves (usually run in odd sizes only from 1-15). Womens or Misses sizes are for those looking for a clean look, not quite as tight fitting as the Juniors clothing (usually run in even size from 2-16).

It is hard to compare sizes due to fluctation in different brands, but usually a young girl that can wear a Girls size 16 MAY be able to also wear a Juniors size 3 or 5. That same girl probably can't wear any size in Women's sizing. 

Also, a teenaged girl that wears a Juniors size 15 MAY be able to wear a Women's size 10 or 12, but will not be able to wear anything sized in a Girls sizing.

I hope this helps some sellers and buyers as to what the difference is between these sizes, but remember, especially as the buyer, ASK FOR MEASUREMENTS if they are not in the auction. Most sellers will be happy to provide you with these to avoid having an unhappy customer and a possible return. If for some reason measurements won't help you or the seller can't seem to give you measurements, I recommend googling (searching the internet itself) by the brand you are interested in. If you find the brand at a store website, it will usually have the brand in the correct location.

For example, if you normally wear a Misses size 12 and are looking at a brand called GLO Jeans in a size 13. I recommend searching for GLO jeans on a search engine. When looking at your search results, you will notice that almost every site mentions "teen" or "juniors" and a couple say "kid". The ABOUT GLO link on the Glo Jeans website itself says that they are manufactured for the Juniors size group.  That tells you that as a 12 Misses, you should not bid on these jeans for yourself.