What is the largest wolf subspecies by weight?

The largest wolf subspecies by weight is the Northwestern wolf. Also called the Mackenzie Valley wolf or Canadian timber wolf, it is a gray wolf subspecies, Canis lupus occidentalis, found across Alaska, western Canada, and parts of the northwestern United States.

Its large body is an adaptation associated with northern habitats, where bigger animals generally retain heat more efficiently. Adult males can weigh roughly 45–68 kilograms, while some exceptional individuals are considerably heavier. The subspecies is also among the longest wolves.

A common mix-up is the Alaskan Interior wolf, which is also exceptionally large and is sometimes described as the second-largest wolf subspecies. Taxonomic revisions have also grouped several formerly separate North American wolf forms under the Northwestern wolf, which can change comparisons between sources. The extinct prehistoric dire wolf and cave wolf were not modern subspecies of the living gray wolf and are not competitors for this answer.