Concept OnePeanuts Snoopy Dad Hat, Adjustable Baseball Cap

Q: My dad has a big head. Will this fit?

I really don’t know how big your dad’s is. So maybe this might help. I wear a 6 3/4 hat, there is at least 4 inches of adjustable to larger at the end of my hat. Might need to google the hat measurements into inches to see how big that makes this cap to reach