Regular physical activity is an important means of promoting health, both in people and their pets. Walking is the most common method used for dogs, but there is a lack of clarity on how much daily activity different breeds of dog require. Data from an online survey of UK dog owners were collected between June and August in 2014. The University of Liverpool Ethics Committee approved the project, and owners consented to data use. The initial dataset (17 028 dogs) was first cleaned to remove erroneous data, and then edited to remove mixed breed dogs, leaving a total of 12 314 dogs from known pedigree breeds. Other information collected included sex, age, neuter status, breed, and amount and frequency of exercise. Exercise frequency and duration were estimated across different breeds, and compared with Kennel Club recommendations, using χ2 tests and binary logistic regression. The online survey data indicated differences amongst breeds in the amount of walking reported (P < 0·001). Afghan hounds were the least exercised breed, whilst breeds reportedly exercised most included: English setter, foxhound, Irish setter and Old English sheepdog. Gundogs were most likely to be walked once per d or more (P < 0·001), whilst smaller dogs were more likely to meet their UK Kennel Club guidelines for dog walking (P < 0·001). The frequency of dog walking varies both within and amongst breeds, and many do not currently receive the recommended amount of exercise. This may constitute a canine welfare problem and also have an impact on the physical activity levels of their owners.