Hill's rise to fame is recounted in 20 Feet from Stardom, a documentary film that tells the untold story of the backup singers behind some of the "greatest musical legends of the 21st century".

A number of Hill's original ballads, including "Desperation" were featured in the 2012 Spike Lee film Red Hook Summer.

[6] After a degree in music composition from Biola University, Hill went to France in 2007 to perform with the French singer Michel Polnareff.

[7] Hill is credited for singing backing vocals and/or choir for Gregg Allman (Low Country Blues); Anastacia (Freak of Nature); Patrizio Buanne (Patrizio); Andraé Crouch (The Journey); Harold Faltermeyer (Copout); Josh Groban (All That Echoes); Taylor Hicks (Taylor Hicks); Carole King (A Holiday Carole); Evelyn "Champagne" King (Open Book); Mike Oldfield (Man on the Rocks); Barry Manilow (15 Minutes); Dave Stewart (The Ringmaster General and The Blackbird Diaries); Rod Stewart (Soulbook); Robbie Williams (Intensive Care); Incubus (Trust Fall (Side A), song "Dance Like You're Dumb").

She is a featured vocalist for albums such as Inspiration: A Tribute to Nat King Cole by George Benson, I'll Take Romance by Steve Tyrell, The Last Ai by Ai and That's Life by Landau Eugene Murphy Jr. She has also provided vocals for soundtracks such as Dr. Seuss' The Lorax: Original Songs from the Motion Picture and Happy Feet Two (Soundtrack).

[10] Hill was the featured singer on Gerard Way's original song titled "Here Comes the End", released July 8, 2020 and which appears on the second season of The Umbrella Academy.

On June 21, 2024, in Minneapolis, The Revolution welcomed Hill as a special guest vocalist when they reunited to celebrate 40 Years of Prince's album Purple Rain.

Joe Lynch of Billboard stated that when she took lead on the yearning, lusty vocal showcase "The Beautiful Ones", "Hill offered up effortlessly silky runs and skyscraping, soulful peaks, absolutely dominating a song that's near impossible to cover.

Along with the rest of the This Is It cast members, Hill performed at Jackson's memorial service at the Staples Center in downtown Los Angeles on July 7, 2009.

In the first episode of the season broadcast on March 25, 2013, she sang "What a Girl Wants" by Christina Aguilera with all four judges, Adam Levine, Shakira, Usher and Blake Shelton pressing their "I Want You" button and turning their chairs.

Said Katy Kroll of Rolling Stone: "It's a sad loss for the show, as Judith had the type of vocal chops and stage presence that should really be rewarded by such a competition.

Hill is the featured vocalist on her composition "Party Rockers" which appears on Gordon Goodwin's Big Phat Band's album Life in the Bubble.

[22] On March 22, 2015, Prince invited representatives from several Minnesota media outlets to preview Hill's debut album at Paisley Park.

Surprisingly, Prince did not discover Hill on The Voice or in the Michael Jackson movie This Is It, where she was featured as a backup singer in rehearsal for his upcoming tour.