Auto-canceling

Comparison of Marth auto-canceling (left) and L-canceling (right) his neutral aerial, demonstrating how even L-cancelling is slower than auto-cancelling.

Zero Suit Samus failing to auto-cancel; she has landed during the middle of her aerial attack, and has thus incurred significant landing lag, thereby leaving her open to punishment.

Auto-canceling is the act of landing during the beginning or ending frames of an aerial attack, thereby circumventing the landing lag that would have occurred had the character instead landed during the middle of that attack's animation.

Auto-canceling an attack produces no more landing lag than a regular landing from an ordinary jump (of which the landing lag tends to be around 4-6 frames, a very short amount of time), whereas landing during the middle of an aerial attack almost always results in a significant delay before the character can act (raise a shield, jump, dodge, etc.) again. Most aerial attacks can be auto-cancelled during both the first few frames and the last few frames of the attack's animation; however, some attacks cannot be auto-cancelled at the start, at the end, or even at all. If an aerial does not have a late auto-cancel window or if the auto-cancel window occurs after the animation has ended, the aerial will auto-cancel once the animation has finished. Each individual aerial attack for every character has a specific auto-cancelling window (or lack thereof) that must be memorized and practiced.

Auto-canceling can be very beneficial to players using characters with laggy aerial attacks, as this can reduce the amount of landing lag produced, and create more time for the character to act, potentially avoiding being punished during the move's landing lag. Precise auto-canceling of aerials is also frequently needed for performing followups and combos, so as to leave less time for the opponent to react and escape.

In Super Smash Bros., auto-cancelling generally has no large impact on gameplay, since L-canceling practically has the same effect although some moves do have extremely lenient auto-cancel windows. A notable example is Ness's down/up aerial which will always auto-cancel. These moves can be used for shield breaks which requires many inputs so the lack of needing to z-cancel makes the shield break significantly easier. All aerials except for Link's up and down aerials are capable of auto-canceling in a short hop.

Super Smash Bros. Melee reduced the effect of L-canceling (now only having the landing lag as opposed to reducing it to 4 frames) making auto-canceling more useful although jumps are shorter than they were in Smash 64 due to gravity being increased across the board and auto-cancel windows are far less lenient across the board making a lot less aerials capable of auto-canceling in a short hop.

Super Smash Bros. Brawl removed L-canceling making auto-canceling more important and useful as while numerous aerials have lower landing lag, none of them had their landing lag reduced enough to completely compensate for the removal of L-canceling. Aerial attacks in Brawl generally have more lenient auto-cancel windows to partially compensate which is further compensated by gravity/falling speeds being much lower than in Melee. A lot more aerials can be auto-cancelled in a short hop in Brawl compared to Melee because of these changes.

In Super Smash Bros. 4, L-canceling continues to be absent, and aerials overall have slightly increased landing lag and later auto-cancel windows, hindering aerial approaches and enforcing a heavier reliance on grounded combat. While some aerials gained the ability the auto-cancel in a short hop, a majority lost their ability to do so either because of their worse auto-cancel windows, the character's lower short hop or both.

In Super Smash Bros. Ultimate, however, since the landing lag on moves has been altered and substantially reduced across the board, aerial approaches have become safer than previously. Aerials are also considerably weaker when performed during a short hop with these changes overall making auto-canceling less useful depending on the aerial. However, many aerials (e.g. Falco's down aerial) have improved auto-cancel windows enabling them to properly auto-cancel in a short hop although naturally, the opposite is also the case with some aerials (e.g. Ike's forward aerial) and some characters are now unable to auto-cancel certain aerials due to their higher gravity reducing the height of their short hop (e.g. Charizard's forward aerial).

Notable examples

The following characters' respective moves have notable auto-cancels.

Smash 64

• Ness: His up aerial and down aerial will always auto-cancel. This allows him to get easy shield breaks along with his DJC (double jump cancel) as well as start long combo strings since his dair has one of the longest lasting hitstun in the game.
• Pikachu: Pikachu's up aerial will always auto-cancel like Ness'. Its large disjointed hitbox and coverage behind and in front of Pikachu make it an effective approach option and defense option. It also combos into itself or into finishing moves such as Pikachu's back aerial. No aerials in subsequent entries can auto-cancel for their entire duration.

Melee

• Donkey Kong: His up aerial's large auto-cancel window allows it to combo into itself, especially against fastfallers.
• Marth: Neutral aerial's large hitbox and long duration make it an effective approach option, especially out of a dash dance. This was retained in Brawl but neutral aerial's auto-cancel window was made far worse in later entries.
• Ness: All his aerials auto-cancel in a short hop. His down aerial auto-cancels as long as the hitbox is not active, making the move frame safe on shield if executed perfectly. This auto-cancel window was retained in Brawl
• Sheik: Forward aerial can autocancel almost immediately after it is initiated, doing so from frame 11 onward, making it one of the safest aerials in the game. It retains this trait in subsequent Smash games although it auto-cancels one frame later in Brawl due to the hitboxes' longer duration.
• Link: Neutral aerial's late auto-cancel starts on frame 32 but it doesn't auto-cancel until frame 40 as the hitbox lasts until frame 39. Despite this, the move still auto-cancels as soon as the hitbox ends which can make the move frame positive on shield if executed perfectly.

Brawl

• Captain Falcon: All of his aerials auto-cancel in a short hop. His down aerial meteor smash has good combo ability, and his Knee Smash can be used to approach and KO.
• Fox: Back aerial has a very lenient auto-cancel window with Fox being able to hit even the shortest characters with it and still auto-cancel the back aerial. Back aerial is a powerful semi-spike making it a good move to use near the ledge.
• Ganondorf: Approaching with his down aerial meteor smash is known as Thunder-stomping, and it has excellent combo ability and KO power as well. Up aerial is also a decent KO option.
• Ike: His powerful back aerial is useful for both approaching and KOing although it is his only aerial which can auto-cancel in a short hop.
• Luigi: All of his aerials auto-cancel from a short hop but more notably, he can perform two forward, up or down aerials in a short hop and he will still auto-cancel them making them strong approach tools on the ground especially forward aerial. His up aerial also had trait in Smash 64 although it along with down aerial lost this trait in Smash 4. His up aerial did regain this trait in Ultimate however.
• King Dedede: Back aerial auto-cancels as soon as its hitbox ends. This should not even occur as the move should have 4 frames of lag before it can auto-cancel but because back aerial's auto-cancel window is listed in the move's script before the command to remove the late hit's hitboxes, it makes the late hit linger for 4 extra frames and removes the hitboxes once the move can auto-cancel. Back aerial is Dedede's best approach option besides his grab and its unintentionally lenient auto-cancel makes his already amazing back aerial that much better.
• Meta Knight: All of his aerials auto-cancel in a short hop. Most notably, his forward aerial's long range and autocancel window give it great utility in relieving pressure, approaching, and comboing.
• Peach: Her forward aerial is a powerful spacing tool and it auto-cancels as soon as the hitbox ends. Her back and down aerials also share this trait.
• R.O.B: All of his aerials auto-cancel in a short hop. Back aerial and down aerial both have extremely lenient auto-cancel windows and they can be used for recovering.

SSB4

• Captain Falcon: Back aerial's range and power make it a useful for approaching, pressuring, starting combos, and KOing.
• Cloud: Both up aerial and down aerial have long hitbox durations and auto-cancel immediately after their hitboxes cease, with the former doing so in a short hop, making them useful for disrupting opponents' approaches and starting combos.
• Fox: Back aerial has one of the most lenient auto-cancel windows in the game, with only a 7 frame window where it will suffer any landing lag. While it does not auto-cancel as reliably as its Brawl counterpart due to Fox's higher falling speed and it is weaker, it is even safer on shield in Smash 4 due to the general increase to shieldstun/shield damage.
• Ike: Forward aerial is a good combo move and spacing tool, and just like Brawl, back aerial is quick and one of his best KO moves.
• King Dedede: While not quite as effective as his previous back aerial, back aerial's range and power make it arguably his best KO move.
• Kirby: Up aerial is an effective juggler due to it's low knockback and angle. Back aerial comes out faster than all of his aerials and is his strongest aerial, making it one of his best KO moves.
• Luigi: As with all previous entries, all aerials auto-cancel from a short hop. Forward aerial is good combo move, and back aerial is one of his better KOing options.
• Mario: Up aerial is great combo move and can lead into Super Jump Punch. Back aerial can Wall of Pain due to its speed.
• Pac-Man: Back aerial is his strongest aerial, and has a significant auto-cancel window on startup.
• Pikachu: Up aerial is very fast and is great for juggling.
• R.O.B: While his back and down aerials have noticeably worse auto-cancel windows, his neutral aerial has a large hitbox, and is effective at approaching, relieving pressure, and starting combos.
• Sheik: Forward, neutral, and back aerials auto-cancel in a short hop. Specifically, forward aerial is one of her best moves due to its abnormally lenient autocancel window, being effective for approaching, pressuring, comboing, and KOing at very high percentages.
• Sonic: Up aerial has a large auto-cancel window coming immediately after its hitboxes cease, making it a low risk move. It is great for combos and KOing near the upper blast zone. Back aerial is Sonic's main KO move and forward aerial is good for edgeguarding. Down aerial auto-cancels after a double jump up B or an up B from the top Battlefield platform, allowing Sonic to land surprise KO's and setup Lock combos.

List of characters who can auto-cancel all aerials in a short hop

Character
Captain Falcon
Daisy	N/A	N/A	N/A	N/A
Dark Pit	N/A	N/A	N/A
Donkey Kong
Diddy Kong	N/A	N/A
Fox
Inkling	N/A	N/A	N/A	N/A
Isabelle	N/A	N/A	N/A	N/A
Jigglypuff
Kirby
Lucario	N/A	N/A
Luigi
Mario
Meta Knight	N/A	N/A
Ness
Olimar	N/A	N/A
Peach	N/A
Pikachu
Pit	N/A	N/A
R.O.B.	N/A	N/A
Rosalina & Luma	N/A	N/A	N/A
Samus
Squirtle	N/A	N/A		N/A
Villager	N/A	N/A	N/A
Yoshi
Zelda	N/A

Trivia

• The forward airs of Donkey Kong in Melee, and of Donkey Kong and Ganondorf in Brawl, Smash 4, and Ultimate before patch 2.0.0, cannot be auto-canceled during their ending frames. By exploring the code of the games and looking at the underlying properties of the moves, it has been discovered that the developers had intended for auto-cancelling those moves to be possible; however, due to a minor error (the accidental use of the wrong type of timing function), those moves auto-cancel significantly later. In Donkey Kong's case, forward aerial should auto-cancel on frame 56 but it instead auto-cancels on frame 82 in Melee and Brawl and frame 78 in Smash 4 (although in theory, it auto-cancels on frame 60/56 due to forward aerial's animation length). In Ganondorf's case, forward aerial should auto-cancel on frame 36 but it instead auto-cancels on frame 55. In Brawl, this also negatively affects his forward aerial's interruptibility making it uninterruptible for 10 frames longer than it should.
• Shulk is the only character in Smash 4 who cannot auto-cancel any of his aerials at all, due to his auto-cancel windows on all of his aerials being programmed after they can be interrupted while their animations have not completed (forward aerial has the least severe case as unlike his other aerials, it can auto-cancel a decent while before the animation has finished and has a strict 3 frame window to be auto-cancelled in a full hop). However, this allows him to cancel an aerial attack's ending lag with another action (jumping, aerial, airdodge). Meta Knight also exhibits this trait with his up aerial in Brawl and multiple other aerials in Smash 4 (such as Ganondorf's forward aerial and Palutena's up aerial) also share this trait.
• Luigi is the only character in the entire series who can auto-cancel all of his aerials out of a short hop in every game despite almost every character in Smash 64 being able to auto-cancel all of their aerials out of a short hop.