I just got one from fin addict last week, about 1-1/2 to 2" long. Small little fella, but has a voracious appetite! I dont believe you can find them any smaller, but I may be wrong. What size tank are you considering putting him into? They can grow quite large very quickly with proper diet, and this shouold be taken into consideration when getting a regal/blue tang..... Mine is in a 110g right now, but he will move into a new 250+ by this time next year, as he will outgrow the 110. Good luck... Erick