Moby Dick is definitely a big whale, but in the end I’m not sure if he can take down the Sharktopus! The Sharktopus isn’t that big, but the Octopus part of him is deadly! One slash and Moby Dick could be done for. Size isn’t always everything in these battles and Moby Dick found that out the hard way. Sharktopus wins.
DReager1.com 
As far as I can tell, Moby Dick seemed to be above average for his species Physeter macrocephalus. Couldn’t give out sizes though, I don’t think Melville was specific and I haven’t read the book in a while.
Yeah, I’ve never read the book but he is supposed to be quite large. The main characters certainly didn’t seem to stand a chance against this beast!
If you’re into that kind of stuff, then go read it. But I must warn you it’s very long and Melville goes on a tangent many times to talk about whale biology.
Yeah, I probably wouldn’t read it anytime soon with that length and all, but one day it could be fun to go through it. Definitely a lot of books ahead of it at the moment tho