SSBU/Frame Data

Speed & Safety

 * Frame - The fundamental unit of time in Smash Ultimate. Because Smash Ultimate runs at 60fps (Frames per second), each frame is 1/60th of a second.
 * Startup - A move’s startup is how long it takes a move to activate in frames. This can be for a hitbox, invincibility, armor, or more.
 * Endlag - A move’s endlag is the amount of time between the last active hitbox on a move, and the move’s FAF
 * Active Frames - A move’s active frames are the frames when a move’s hitbox is out
 * Shield Safety - Shield safety is a measure of how punishable an option is if it hits a shield. Often measured in frames, shield advantage is an important part of a tool’s shield safety. If a move is “-9 on shield”, that means the attack has a disadvantage of 9 frames upon hitting a shield, and can be punished by any option that is frame 9 or faster while also having the range to reach. For more details, see Out-Of-Shield (OOS) in the Defense system.
 * Perfect Shield (Parry) provides an option to make escaping shield easier, giving the blocker up to 12 frames more advantage, while also skipping the shield-drop animation. For more details see Perfect Shield in the Defense system.

Canceling Moves

 * First Actionable Frame (FAF) - FAF is the term for when a move can be canceled into most options a character can do. There are a few options that a move cannot be canceled into at it’s FAF, but instead must wait for a move’s animation or IASA window to end; these exceptions are:
 * Canceling multi-press normals (such as jabs) into other normals during an IASA window
 * Canceling multi-press specials (such as Marth’s Dancing Blade) into other specials during an IASA window
 * Footstooling an opponent
 * Being put into a footstool animationverify
 * Being put into a pickup animation such as Pyra’s Blazing End returning, or picking up an Assist Trophy or Hammer item.
 * Interruptible As Soon As (IASA) - IASA is a term originally meaning the same thing as FAF in older smash games, but in Ultimate is often used for the window in which a move can be canceled into another move, such as a Jab 1 into a Jab 2, or Ness’s Down Tilt into another Down Tilt. It still is sometimes used interchangeably with FAF, however.
 * Attack Cancel (AC) - Attack Cancel is the action of canceling an attack into another move. Tilt attacks and Dash attacks can be canceled into an aerial by jumping during the first two frames, and Dash Attacks can be canceled into a grab during the first 2verify frames. Using Attack Cancel to turn around and perform an aerial is a common use for it, as by performing a reverse Forward tilt to turn around, and then canceling it with a jump, one can use a back aerial facing forwards.