Johnson's work has been translated into French, Dutch, Japanese, Spanish, German, Italian, Hebrew, Polish, Portuguese, Catalan and Serbian and focuses on characters at the edge of society for whom isolation and disconnection are nearly permanent conditions. Michiko Kakutani described the central theme "running through his tales is also a melancholy melody of longing and loss: a Salingeresque sense of adolescent alienation and confusion, combined with an acute awareness of the randomness of life and the difficulty of making and sustaining connections."
According to Daniel Mendelsohn, writing for New York Magazine, “Johnson's oh-so-slightly futuristic flights of fancy, his vaguely Blade Runner–esque visions of a cluttered, anaerobic American culture, illustrate something very real, very current: the way we must embrace the unknown, take risks, in order to give flavor and meaning to life.” A strain of absurdity also runs through his work, causing it to be described as "a funky new science fiction that was part irony and part pure dread." "Teen Sniper" is about young sniper prodigy enlisted by the Palo Alto police department to suppress the disgruntled workers of Silicon Valley. "The Canadanaut" follows a remote team of Canadian weapons developers who race to beat the Americans to the moon.