What size gas chainsaw do I need for cutting firewood?

Across the reviewers we read, a 50-60cc saw with an 18-20 inch bar (such as the Husqvarna 455 or 460 Rancher) is the consensus sweet spot for bucking firewood and felling medium trees. Smaller 38-40cc homeowner saws like the Husqvarna 120, 135 and 440 handle limbing and trees up to roughly 8-12 inches but specialist-community threads note they bog down in larger hardwood.