What size and weight heavy bag should a beginner buy?

For adults, reviewers generally point to roughly a 70-inch freestanding bag or an 80-100 lb hanging bag. Lighter bags swing or tip excessively; heavier bags feel more realistic but require solid mounting. Beginners working technique and fitness are usually steered toward complete freestanding kits, while anyone planning to hit hard is pushed toward a filled 100 lb hanging bag.