Weight

Weight is a measure of how far a character can be knocked back horizontally by an attack, if damage is held constant. It also affects vertical knockback in concert with falling speed.

It is usually considered an advantage for a character to be heavy; however, extra weight can make characters slightly more susceptible to combos. A notable example in Melee is that characters with lower than 87 weight fall down when hit by Fox's shine, and thus are invulnerable to his shine combos.

SSB Weight Ranking
This is the ranking of characters in the first installment. It was recently calculated by Blue Ninjakoopa and is listed from heaviest to lightest.

SSBM Weight Ranking
Following are the characters in Super Smash Bros. Melee, ranked in order of heaviest to lightest. This list is based on horizontal knockback on the Mushroom Kingdom 2 weight scale and is featured on Mew2King's website of statistics. Mew2King credits Blake Mutschler and Aaron Kurtz for having calculated these data. The Metal Box multiplies a character's base weight by 3, the Super Mushroom by 8/5ths, and the Poison Mushroom by 5/8ths.

SSBB Weight Ranking
Firstly, for the purpose of calculation of knockback, every character has two associated constants, namely weight1 and weight2 Here is the order of characters' weights in Brawl. These weights were calculated by MrSilver. and ColinJF