You can burn around u003ca href=u0022https://www.dhs.wisconsin.gov/publications/p4/p40109.pdfu0022 target=u0022_blanku0022 rel=u0022noreferrer noopeneru0022u003e200–300 caloriesu003c/au003e when swimming moderately for 30 minutes. The number of calories can depend on several factors like your weight and exercise intensity. Losing weight also requires you to consume fewer calories than you’re burning.