"In a Perfect World…" received generally positive reviews from music critics. At Metacritic, which assigns a normalized rating out of 100 to reviews from mainstream critics, the album received an average score of 65, based on 13 reviews. AllMusic's Andy Kellman commented that the album "reflects the versatility Hilson demonstrated prior to its release. It's a songwriting showcase as much as it is a coming out for a full-blown artist, yet more about what Hilson can do than who Hilson is". "Entertainment Weekly"s Margeaux Watson called it "a seductive debut CD full of slick, radio-friendly cuts". Jody Rosen of "Rolling Stone" found its songs "uniformly excellent. Hilson's halfway there — she just needs a lil' more personality". Quentin B. Huff of PopMatters shared a similar sentiment, perceiving Hilson's songwriting as impersonal, and wrote "As a whole, the album suffers from an overriding sense of sameness, of mood as well as in relation to the current R&B landscape. [...] it’s a bit melodramatic in places and maybe a touch too hip for its own good". Rob Sheffield of "Blender" wrote that Hilson "comes across as fresh on her long-delayed debut."