Gunter also had offers from Vanderbilt, Hawaii, Nevada, New Mexico, Utah State and Wyoming, according to various recruiting websites.
He visited Vanderbilt of the SEC last week, nearly two months after his official campus visit to BYU.
Rivals.com and Scout.com both have Gunter listed as a three-star recruit.
Gunter's commitment brings BYU's total to 21 and comes on the heels of a commitment from Bingham High defensive end Langi Tuifua over the weekend.
The Cougars are still in the running for several high-profile recruits, including Bingham five-star defensive tackle Jay Tufele, Iowa City (Iowa) four-star receiver Oliver Martin and Westlake four-star safety/receiver Chaz Ah You.
Sitake did receive some bad news this week as well. Tight end Cameron Latu, a member of the 2018 signing class (this year's juniors) from Salt Lake City's Olympus High noted on Twitter that he has decommitted from BYU.
Here's the updated list of BYU's 21 commits:
BYU's 2017 Commits (21)
Jackson McChesney, 6-0, 170 RB from Highland, Utah (Lone Peak High School)
Isaac Rex, 6-4, 225 TE from San Clemente, Calif. (San Clemente High School)
Tanner Baker, 6-5, 225 DE from Acworth, Georgia (Allatoona High School)
Preston Lewis, 6-2, 225 DE from Highland, Utah (Lone Peak High School)
Ammon Hannemann, 6-2, 190 safety from Highland, Utah (Lone Peak High School)
Donovan Hanna, 6-5, 230 TE from Queen Creek, Ariz. (American Leadership Academy)
Ben Bywater, 6-3, 205 OLB from Salt Lake City, Utah (Olympus High School)
Tariq Buchanan, 6-2, 175 DB from Elgin, Texas (Elgin High School)
Seth Willis, 6-6, 315 OL from Newtown, Connecticut (Newtown High School)
Bentley Hanshaw, 6-6, 225 TE from Moorpark, Calif. (Moorpark High School)
Tongi Langi, 6-1, 180 DB from South Jordan, Utah (Bingham High School)
Ryan Rehkow, 6-4, 190 K from Versdale, Wash. (Central Valley High School)
Keenan Ellis, 6-1, 170 WR/DB from Chula Vista, Calif. (Bonita Vista High School)
Tyler Batty, 6-5, 220 DE from Payson, Utah (Payson High School)
Paula "Mango" Finau, 6-4, 330 OL from Wailuki, Hawaii (Baldwin High School)
Seleti Fevaleaki, 6-2, 250 DL from Corona, Calif. (Centennial High School)
Ula Tolutau, 6-1, 230 RB from Salt Lake City, Utah (East High School)
Joe Tukuafu, 6-4, 230 TE from Salt Lake City, Utah (East High School)
Langi Tuifua, 6-3, 230 DE from South Jordan, Utah (Bingham High School)
D'Angelo Gunter, 6-2, 180 DB from San Diego, Calif. (Del Norte High School)
John Vaka, 6-4, 270 OL from Oakland, Calif. (Diablo Valley College)