Crabbe's poetry was predominantly in the form of heroic couplets, and has been described as unsentimental in its depiction of provincial life and society. John Wilson wrote that "Crabbe is confessedly the most original and vivid painter of the vast varieties of common life that England has ever produced;" and that "In all the poetry of this extraordinary man, we see a constant display of the passions as they are excited and exacerbated by the customs, laws, and institutions of society." The Cambridge History of English Literature saw Crabbe's importance to be more in his influence than in his works themselves: "He gave the poetry of nature new worlds to conquer (rather than conquered them himself) by showing that the world of plain fact and common detail may be material for poetry".
Although Augustan literature played an important role in Crabbe's life and poetical career, his body of work is unique and difficult to classify. His best works are an original achievement in a new realistic poetical form. The major factor in Crabbe's evolving from the Augustan influence to his use of realistic narrative was the changing readership of the late 18th–early 19th century. In the mid-18th century, literature was confined to the aristocratic and highly educated class; with the rise of the middle class at the turn of the 19th century, which came with a growing number of provincial papers, the heightening in production of books in weekly installments, and the establishment of circulating libraries, the need for literature was spread throughout the middle class.
Narrative poetry was not a generally accepted mode in Augustan literature, making the narrative form of Crabbe's mature works an innovation. This was due to some extent to the rise in popularity of the novel in the late 18th–early 19th century. Another innovation is the attention that Crabbe pays to details, both in description and characterization. Augustan critics had espoused the view that minute details should be avoided in favor of generality. Crabbe also broke with Augustan tradition by not dealing with exalted and aristocratic characters, but rather choosing people from middle and working-class society. Poor characters like Crabbe's often anthologized "Peter Grimes" from The Borough would have been completely unacceptable to Augustan critics. In this way, Crabbe created a new way of presenting life and society in poetry.