[5] The Guardian's Alexis Petridis noted that the record works least when going for "straightforward hip-hop" through Kid Sister's limited everyday lyricism but gave it praise for being "a great pop album" with "Ed Banger-inspired nu-rave synthesisers" and immediate choruses, concluding that: "Either way, Ultraviolet seems worth celebrating for what it is, rather than what people thought it should be.

"[10] AllMusic's David Jeffries felt the producers overshadowed Kid Sister on her own record but she manages to deliver memorable quips throughout the track listing, highlighting "Pro Nails" and "Get Fresh" for having "slang queen rhymes" and a "brassy enough delivery", saying that "Ultraviolet isn't the "ladies first" declaration that was hoped for, or the redefinition of party-rap that was hinted at, but it's still highly recommended for party people.

"[6] Nat Thomson of XXL gave credit to the Estelle and Cee-Lo features for allowing a break from the "dance-heavy" material that gets tiring towards the end, concluding that: "Save for the occasional spunky, flirtatious zinger, don't look for Ultraviolet to appease hungry listeners looking for lyrical food for thought.

"[18] Paste contributor Brian Howe called the record "undeniably solid" for its "ear-wormy club bangers" and Kid Sister's "pugilistic" and "resilient" flow over them but was critical of the limited subject matter and its untimely release feeling outdated.

"[20] Tom Breihan from Pitchfork felt that Ultraviolet lacked "a restless, inventive sense of fun" compared to similar projects like Spank Rock's YoYoYoYoYo and FannyPack's So Stylistic, criticizing Kid Sister's rapping skills for being bereft of intense delivery or different topics besides partying.