After the experience working with American musician Tim Presley as DRINKS, Le Bon changed her working method. She created short demos and used different instruments. Lyrics were written after the music had been completed. She described the process as "the songs were mapped out in my head and I had vocal melodies, just not lyrics".[3] When the songs had been developed, they were rehearsed over five days together with Stephen Black (bass), H. Hawkline (guitar) and Stella Mozgawa (drums).[3] Upon entering the studio, recording was completed over five days after which Le Bon completed her vocals and overdubs. It was followed by the process of selecting the songs and running order for the album.[3]
Crab Day received positive reviews from contemporary music critics. At Metacritic, which assigns a normalized rating out of 100 to reviews from mainstream critics, the album received an average score of 75, based on 21 reviews, which indicates "generally favorable reviews".[4]
Laura Snapes of Pitchfork Media gave the album a favorable review, stating, "Crab Day is a voyage into doubt led by a queasy compass, and a ringleader who's prepared to stake out uncertain territory. Le Bon always keeps you guessing, making the old traditions of guitar-oriented rock feel arbitrary, too. Her nervy assessments of the world are filled with equal parts suspense and heart, and beautifully zany riffs, where the feeling of being frayed by uncertainty comes together into a strangely comforting patchwork."[13]