After several small roles, she starred as a child prodigy in Gifted (2017), a breakthrough for which she received a nomination for the Critics' Choice Movie Award for Best Young Performer.

In 2022, Grace wrote, executive produced, and starred in The Bad Seed Returns, and portrayed Jan Broberg in A Friend of the Family.

After signing with Photo Finish Records in 2020, Grace released her debut single, "Haunted House", in 2021, as part of the Ghostbusters: Afterlife soundtrack.

[6] Grace first expressed interest in acting at age four, after she received a collection of DVD films starring Shirley Temple from her great-grandmother.

After Grace secured parts in Crash & Bernstein (2012–2014) and Goodbye World (2013), her family moved to the city, with her father having a residency in Ventura.

[16] TVLine included her appearance in a list of the best flashback castings on television: "It's one thing to look like the younger version of a character, but Grace even cried like Caroline".

[36] Grace appeared in the 2018 horror drama The Bad Seed, a remake of the 1956 film of the same name, itself an adaptation of William March's 1954 novel.

[39][40] According to The Hollywood Reporter, Grace's ability to be "unnerving, sweet and occasionally funny" is key to the success or failure of The Bad Seed, and "she nails every beat";[41] similarly, The A.V.

[44] In the same year, she made a guest appearance on the supernatural horror show Chilling Adventures of Sabrina's holiday special entitled "A Midwinter's Tale".

[45] According to the series creator, Roberto Aguirre-Sacasa, Shipka immediately suggested Grace for the role after hearing a pre-teen Sabrina would appear on the show.

[46] During this time, she began recurring on the CBS sitcom Young Sheldon as Paige Swanson, a child prodigy and rival to the titular character.

The first of these was a comedy-drama titled Troop Zero, which features Grace as a misfit girl who wants to send messages to space and enters a nationwide competition alongside a group of Birdie Scouts.

[55][56] Grace's final release of 2019 was the supernatural horror film Annabelle Comes Home, which became the seventh installment in The Conjuring Universe.

[62][63][64] According to The New York Observer, the "terrific" Grace had her own unique interpretation of the "horror movie kid" cliché that suits the "twisted age in which we find ourselves".

[67][68] In 2021, Grace began recurring on the Hulu dystopian series The Handmaid's Tale, an adaptation of the 1985 novel of the same name, as Esther Keyes, an intelligent and rebellious 14-year-old who has been abused, raped, and married off to an older Commander.

[72] Entertainment Weekly commented that Grace had "a memorable turn as a tyrannical child bride",[73] and Den of Geek commended her "remarkable self-possession".

[83][84] Mark Feeney of The Boston Globe asserted that "[Ghostbusters: Afterlife] has its moments, most of them owing to a quite-phenomenal Mckenna Grace",[85] and Gizmodo considered her performance "instantly unforgettable[,] ... truly revelatory, [and] star-making".

[89] Grace, who reprised her role as Emma, found acting her own script to be a unique experience: "It wasn't my interpretation of someone else's writing or character ...

[97] A Friend of the Family premiered on October 6, 2022, to positive critical reviews;[98] Common Sense Media argued that "Grace does a terrific job conveying the mixture of vulnerability and growing dread her character is experiencing".

[99] The following year, Grace starred in the science fiction adventure film Crater, playing Addison, the daughter of a respected scientist from Earth.

[111] Grace is set to appear in Jan Komasa's Anniversary, a thriller about a very close family split apart by a new movement;[112] Amy Wang's Slanted (2025), a satirical drama;[113] Nobody 2 (2025);[114] and Scream 7 (2026).

[123] Commenting on Grace's performance in Gifted, Bill Goodykoontz of USA Today described her as "the rare child actor who doesn't seem like she's trying to hit emotional marks".

[124] Marc Webb, who directed Grace in Gifted, praised her comedic timing, which he described as "a different kind of sophistication that is very deep and very pure and really sincere".

[7][97] Grace signed with Photo Finish Records in 2020 and released her debut single, "Haunted House", alongside a music video in November 2021.

[132] Preceded by the songs "Post Party Trauma",[133] "Ugly Crier",[134] and "Checkered Vans",[135] Grace's debut extended play (EP), titled Bittersweet 16, was released on March 3, 2023.

[136] She identified Swift and Lana Del Rey as her key music influences because of their storytelling and the relatable, vivid imagery in their lyrics.

[7] Grace decided to start writing her own music after listening and emotionally connecting to Conan Gray's album Kid Krow (2020) during the COVID-19 pandemic.

[136] Bittersweet 16 has a pop rock and pop-punk sound,[145][146][141] with its songs discussing themes of heartache, body image, and social anxiety.

According to Variety, Grace's carefully monitored social media had an additional layer of self-protection since it lacked the "everyday, confessional transparency" that was the standard for her generation.

[126] According to the review aggregator site Rotten Tomatoes, Grace's most critically acclaimed films include Frankenstein (2015), Gifted (2017), I, Tonya (2017), Captain Marvel (2019), Troop Zero (2019), Annabelle Comes Home (2019), Ghostbusters: Afterlife (2021), and Crater (2023).