How big will my rats get?

[WinX]

I've had my two girls for a while now: Winx is almost 6 months and I've had her for 4 months so far. And Pixie is 7 months and I've had her for three months. I've visited a few pet stores and some pet adoption places (just to look) and the rats they have are huge compared to mine. The girls have definitely grown since I got them but when should I expect them to get really big? I'll post pictures to help with the size comparison, but I was just curious around what age are they "fully grown?"

[lilspaz68]

Personally I think a rat gets its full growth about 1 year old.  I have heard 8 months but I think they still have some of that youthful lean look.
Each rat is different.  I adopted 3 girls from a shelter and they were quite small.  I fed them good food, gave them lots of love and exercise and they grew quickly.  1 stayed medium sized, another was a bit bigger and the last one is quite a big girl.  They hit their full growth about 9 months.