A jump is an action that moves a character from the ground into the air. It is performed by pressing up on the Control Stick/D-Pad, the X or Y buttons with the GameCube, Classic Controller, and the 3DS, or the C button on the Wii Remote and Nunchuk. All characters can also jump a second time in midair, providing they are not attacking, air dodging, helpless, in hitstun, or have used it already.
A few characters can jump more than once in the air:
There is a short delay between the jump button being pressed and the on-screen character actually jumping, during which the onscreen character will enter a crouching portion of their jumping animation. If the control stick or jump button is released during this time, then the character short hops. If the control stick is tilted backwards during this time, the character will jump backwards with a different animation than a regular jump. If the standard attack button is pressed during this time, then the character uses their up smash (but only if the jump was executed with the Control Stick). Because characters can jump while shielding (excluding Yoshi in Super Smash Bros. Melee and Super Smash Bros. Brawl, due to his unique shield), this allows usage of up smashes (and up special moves as well) without having to drop the shield. This also makes it difficult for a player using the Wii Remote-only control scheme to perform up tilts. Inputting an aerial on the first frame that a character is airborne will cause the jump to be slightly lower, because gravity applies to the first frame of an aerial but not to the first frame of a jump.
Brawl added a jumping mechanic known as footstools. This allows characters to jump off the heads of other characters. This can be done even when all midair jumps have already been used.
In Super Smash Bros. Ultimate, a character will emit a subtle wispy trail if they have no extra jumps available.
Also known as jumpsquat, each character has a different window of time where they crouch before they jump. Characters that leave the ground faster can transition between their air and ground games easier; however, depending on the control setup, they may find it more technically demanding to perform short hop or up smash.
The below values apply only to regular brawls; in The Subspace Emissary, all characters jump two frames faster.
*These characters' jumpsquat values are defined as 6 in fighter_param.bin, though they actually end up being 7.
Every character has a 3 frame jumpsquat.
Jump height ranking
Below are characters ranked by the height of their first jump.
Note that there are two methods to encode jump height, depending on the game.
Super Smash Bros.
The jump physics of Smash 64 are significantly less understood than later games due to extra complexity in the data. It is currently believed that there are two values involved in a normal jump: a base jump force, and an additional jump force based on how much height is given to the Control Stick. Until this is more elaborated, only the typical maximum jump force is listed here.
The calculation of short hop jump force is currently unknown.
Super Smash Bros. Melee
Super Smash Bros. Brawl
The following is a ranking of the characters in Super Smash Bros. Brawl based on how high they jump from the ground, along with the jump force of each character.
Super Smash Bros. 4
Super Smash Bros. Ultimate
Super Smash Bros. for Wii U digital manual description