Wingspan 35-60 mm. A favourite of genetic studies, this species shows well the phenomenon of industrial melanism, where all-dark individuals became the dominant form in certain parts of northern England. Nowadays, the melanic form  carbonaria is declining again in these areas.

Found in a range of habitats.

The flight period is from May to August.

The larvae feed on a range of trees and plants.

Common throughout most of Britain though more locally distributed in Scotland. In a recent survey to determine the status of all macro moths in Britain this species was classified as common.

Fairly common in Leicestershire and Rutland. L&R Moth Group status = A (common and resident)