The baby's name is an apparent nod to albums Culture and Culture II from Migos, the rap group of which Offset is a member. "Kulture Kiari Cephus 07/10/18", she wrote, tagging her husband Offset (true to form, we got the idiosyncratic Dominican celebrity name locked in).
Cardi plans to resume her tour with Bruno Mars, with Kulture in tow.
The couple was secretly married last September.
TMZ obtained the their marriage license that was filed in Fulton County, Georgia, on Monday, June 25.
It's been a big year of announcements for the rapper. They named her Kulture Kiari Cephus.
Offset is also a father to three other children from previous relationships - two sons, Jordan and Kody, and a daughter, Kalea Marie. "My sh*t is going to start at 9 p.m. because that's how I celebrate, that's how Caribbean people celebrate", she said.
Offset and Cardi B's bundle of joy has arrived! Wearing a tight-fitting white gown, the "I Like" it rapper took the stage to perform her song "Be Careful" bearing a very obvious baby bump.
The Bodak Yellow star told fans her daughter was born four days ago on 7 July.