Attack damage

Attack damage (or AD) directly increases the physical damage of a unit's autoattack and also improves the damage some champion abilities do. Every champion starts with some base attack damage that increases each level. Additionally, several items and champion abilities, as well as spells, buffs, runes and masteries grant bonus attack damage. The champion's total attack damage is the base attack damage plus the bonus attack damage.

This statistic stacks additively in most circumstances. When there are percentile attack damage bonuses, they are first added together if there are several sources and then they multiply the total attack damage of the champion.

At level 18, base attack damage ranges from  to  ( and ).

Champion abilities
Note: Only the attack damage bonus effect of these abilities is shown here, to read more information on each of these abilities, follow the link on each of them.
 * increases his attack damage by for 7 seconds.
 * increases his attack damage by plus  for 5 seconds.
 * increases her attack damage by.
 * passively increases his attack damage by . He can activate this ability to increase his attack damage by instead and nearby allied champions' attack damage by half of that amount for 7 seconds.
 * increases his attack damage by for 20 seconds.
 * passive gains attack damage equal to of his bonus movement speed.
 * increases an allied unit's attack damage by for 5 seconds.
 * increases his attack damage by for 6 seconds.
 * passively increases his attack damage by when the ability is not on cooldown and grants double that bonus for 10 seconds on activation. It is possible to have both bonuses activated if the cooldown gets refreshed during those 10 seconds
 * grants him 6.375% of the damage it deals as attack damage.
 * grants him attack damage as long as he is on the trail created by the ability.
 * increases his attack damage by  for 6 seconds.
 * increases her attack damage by when she is hit by an attack or hits an enemy. This buff lasts for 5 seconds and stacks up to 10 times. She can activate this ability to gain max stacks.
 * passively increases his attack damage by 25% of his armor.
 * increases her attack damage by 20% for 15 seconds.
 * increases his attack damage by for as long as the ability is toggled on.
 * increases the attack damage of nearby allied champions by while active and persists for 1 second after deactivation.
 * increases his attack damage by and half of that to nearby allied champions for 10 seconds.
 * increases his attack damage by for 8 seconds.
 * passively increases his attack damage by plus  per 1% of his maximum health missing.
 * increases his attack damage by for 7 seconds.
 * increases his attack damage by while active.
 * increases her attack damage by for 10 seconds.
 * passively increases his bonus attack damage by

Masteries

 * increases your champion's attack damage by.
 * increases your champion's attack damage by per level ( bonus attack damage at level 18).

Runes

 * and runes increase attack damage.

Neutral buffs

 * The buff grants 40 bonus attack damage for 4 minutes.
 * The buff increases attack damage by a percentage equal to the champion's level up to a maximum of 18%.

Champion's abilities
Note: Only the attack damage reduction effect of these abilities is shown here, to read more information on each of these abilities, follow the link on each of them. Effects that reduces damage is not the same as decreasing a champion's attack damage.


 * decreases surrounding enemy champions' attack damage by for 4 seconds.
 * reduces the opponent's attack damage by for 8 seconds.

Neutral Debuff

 * Voracious Corrosion reduces a champion's attack damage by 50%.

List of champions' attack damage
increases his attack damage by 25% of his armor. This includes his base armor and is an innate passive ability thus essentially increasing his base damage unlike all other ranked champion abilities which are temporary or situational boosts to damage. The increase to Rammus' damage is at level 1 for a total of  and  at level 18 for a total of.

,, and are abilities that passively increases their respective champions' attack damage. They are ranked abilities and thus cannot be counted on for a bonus at level 1. However, arguments could be made that at level 18 they will have 5 ranks and thus this will increase their damage permanently.
 * raises 's total attack damage to.
 * raises 's total attack damage to a minimum of.
 * raises 's total attack damage to.

Trivia
AD can become negative. Auto attacks will deal no damage in this case.

The maximum attack damage attainable from Attack Damage equipment and buffs:
 * Summoner's Rift
 * 5005
 * 110
 * 10
 * 40
 * Total attack damage660
 * Dominion
 * 95
 * 4005
 * Total attack damage495
 * Twisted Treeline
 * 95
 * 4005
 * 42
 * +10%2Twisted Treeline Altars
 * Total Attack Damage590.7
 * 537 without the altars

The optimum attack damage from runes and masteries:
 * 3
 * 9
 * 21.06Greater Marks of Might
 * 9.72Greater Seals of Might
 * 6.48Greater Glyphs of Might
 * 13.5Greater Quintessence of Might
 * Total Attack Damage62.76

The optimum attack damage attainable from allies, not including the listed champions:
 * 20
 * 50
 * 20
 * 35
 * Total Attack Damage125
 * For Twisted Treeline, it would only be 93 due to the team size limit.

With 5, grants 95 attack damage.
 * Combined with, Olaf can achieve 194 attack damage.
 * Combined with, Sion can achieve the highest attack damage in the game.
 * Note that the bonus AD stated above does not include base health, health from runes and masteries, or health gained from abilities (, and.

Excluding that can get an unlimited attack damage using  and,  can achieve the highest possible attack damage in the game, but only lasts 6 second due to :
 * 117Base AD at level 18
 * 133 / 93Allied champiopns
 * 63Runes and masteries
 * Total attack damage313 / 273
 * Summoner's Rift AD973
 * With 1362
 * Dominion AD808
 * With 1131
 * Twisted Treeline AD850
 * With and 2 altars1309

can achieve the second highest possible attack damage in the game, but only for a split second during the end of his :
 * 116.3Base AD at level 18
 * 300
 * 133 / 93
 * 63{{larr}Runes and masteries
 * Total attack damage612.3 / 572
 * Summoner's Rift AD1272
 * Dominion AD1107
 * Twisted Treeline AD1,149
 * With 2 altars1,264

has holds a more "sustainable" third place with:
 * 111Base AD at level 18
 * 105 (combined active and passive, achievable upon scoring a kill with .)
 * 133 / 93
 * Total attack damage412 / 372
 * Summoner's Rift AD1072
 * Dominion AD907
 * Twisted Treeline AD949
 * With 2 altars1,044

SivHD surpasses all three using, see: here. He achieves 1577 AD and 4153 movement speed. However, it is not currently known how this was possible given known rules regarding movement speed. Using the given information, only the following was calculated:
 * 3404
 * SivHD claims that due to Bloodthirsters losing stacks, would be more efficient. This is incorrect. A Bloodthirster only loses half its stacks on death, reducing from full stacks down to 80. Gaining 5 kills post-death would increase this back up to 85.
 * 110
 * 10 (not used by SivHD)
 * 8 (allied)
 * 107Base attack damage
 * Total Attack Damage575
 * Due to use of Revive, use of is not possible and obtaining  or  would not be feasible.
 * 320Base movement speed
 * 130
 * 75% (stacks multiplicatively)
 * 50%
 * 40% (Mantra)
 * 55%
 * 52%
 * 3%
 * 2%
 * 125% with (stacks multiplicatively)
 * 35% with
 * 40%Ally's
 * 15%
 * Total percentage bonus492%
 * Raw movement speed2420
 * Actual movement speed1440 (1120 bonus)
 * Bonus AD from 280
 * Total attack damage855
 * Calculated damage using SivHD's build825 (much less than 1577 as shown).
 * Note SivHD's build has higher on-hit damage due to 100% Critical Strike Chance from 4, although the given AD is lower.

For SivHD's video to be possible, one or more of the given movement speed bonuses are stacking multiplicatively rather than additively. (Note: It is known that movement speed bonuses from some abilities stack multiplicatively, but it is not yet documented which ones do or do not, or if all of them do.)