how big is the average human heart
1 A human heart is roughly the size of a large fist. 2  The heart weighs between about 10 to 12 ounces (280 to 340 grams) in men and 8 to 10 ounces (230 to 280 grams) in women. 3  The heart beats about 100,000 times per day (about 3 billion beats in a lifetime).