How Old Is My Little Fry Guy?

[GuppyGoddess]

Today I brought home a new guppy. He (or she) a baby about 1/3-1/2" long. The picture isn't the best and it's kind of hard to see the tail through the plastic. Maybe with the quarter next to him in comparison, it may be easier to determine his age.

I forgot to ask the petstore! Any idea?