She won a Pulitzer Prize for Feature Writing in 2018 for her profile of white supremacist and mass murderer Dylann Roof, as well as a National Magazine Award.

Ghansah has drawn particular recognition for her longform profiles of subjects such as Kendrick Lamar (in the Los Angeles Review of Books),[8] Missy Elliott,[9][10] Jean-Michel Basquiat,[11] Chirlane McCray,[12] and Toni Morrison[13]—which Flavorwire recommended as "necessary, even recuperative"[14]—as well as essays on Beyoncé's fans,[15][16] Jimi Hendrix's Electric Lady Studios,[17] and James Baldwin's historic home in southern France.

"[21] Her writing has earned praise from The Atlantic,[22] The New Yorker,[23] and Brooklyn Magazine whose editors wrote that "if we wanted to compile a reading list of the best journalism in the last couple of years, we'd begin with basically all the work of Rachel Kaadzi Ghansah.

"[33] For the MoMA, in 2018, Ghansah curated a PopRally event entitled "Woman's Work" a celebration of black womanhood and black female genius that featured the work of Julie Dash, Kandis Williams, and dream hampton, music from Helado Negro, readings from Greg Tate, Saeed Jones, Darryl Pinckney, and a performance from Steffani Jemison and Sharifa Rhodes-Pitts as FORT.

[34][35] In 2019, Ghansah was a recipient of the American Mosaic Journalism Prize, a $100,000 award from the Heising-Simons Foundation for her "deeply reported and essayistic writing pushes the form of longform journalism, ranging from a poignant profile of master painter Henry Taylor to a searing exposé of the hotbed of racism and white supremacy that fueled the heinous murder of nine African-Americans in Charleston, South Carolina.

Her power of observation and nuanced writing both shines light on Black Americans and dares us to look at the forces that shape race in America.

"[39] Kevin Sack, writing in The New York Times, called the piece "expansive and intimate", saying "Ghansah guides us through what is known of the life this young man who remains 'safeguarded by his knowledge that white American terrorism is never waterboarded for answers.

[43] "For an unforgettable portrait of murderer Dylann Roof, using a unique and powerful mix of reportage, first-person reflection and analysis of the historical and cultural forces behind his killing of nine people inside Emanuel AME Church in Charleston, S.C."[44] However, Adam Lankford, a criminology and criminal justice professor at the University of Alabama who researches mass shootings, said he respects Ghansah and her skillful work, since in-depth investigations like this story can help academics find patterns and make antidotes to America's mass shooting epidemic, but he also wishes Ghansah knew how dangerous it is to publish mass shooters' names and photos.