The former Fleetwood Mac singer returned the compliment after performing a beautiful version of Fleetwood Mac's "Landslide," telling host Nick Cannon that VanderWaal has a bright future.
"I have been watching this show from the very beginning," she said, "I have to say she reminds me a lot of me in a lot of ways. We sing very similar ... we like to be weird and quirky and we like to be a little different ... and not like anybody else."
VanderWaal's individuality will take her far.
"She's got it," she said. "Whatever happens Grace is going to the top."
After the show on Tuesday night, judge Howie Mandel told Billboard that the record industry is already scouting his Golden Buzzer pick.
Grace VanderWaal, 12, Rocks 'America's Got Talent' Finale With Original Song: Watch
"The biggest people in the music business are calling and saying, 'Is she tied up? Would she do something with us? Do you know anything about it? Is this Simon's label?' I've never had that before," he said.
But is VanderWaal the next Taylor Swift? Swift's label, Big Label Machine Records, declined comment, but Chris Booker, afternoon jock at Los Angeles radio station KAMP, said signing VanderWaal would be a slam dunk for any record company.
"I know, it's putting a lot on the line when you include an unknown 12-year-old girls name into the same sentence as a Taylor or an Adele, but I just did it," he said. "Her talent simply doesn't make sense. How is such perfection coming from that tiny little lady? She lights me up. I just don't see how she doesn't become a household name."
Booker also said her songs are instant classics.
"While all wildly original, her songs all feel instantly comfortable," he said. "When you hear them for the first time, you'd swear that you'd grown up with them."
That said-is it a risk for a label to sign someone so young?
"Where's the risk? She's like buying Apple stock in 1980," he said. "Duh.. 'The Amazing Grace.'"