Attack damage

Attack Damage (or AD) directly increases the physical damage of a champion's autoattack. Bonus damage is calculated before damage reduction from armor. This statistic scales additively; meaning that each bonus point acquired directly affects the statistic. The total amount of physical damage is calculated by basic damage + bonus damage.

At level 18, base attack damage ranges from 93 to  130.

Ways to Increase Bonus Damage

 * +8 Attack Damage (to nearby allied champions, UNIQUE Aura). +270 Health, +18 Armor, +24 Magic Resistance, UNIQUE Aura: +12 Armor, +15 Magic Resistance to nearby allied champions. 1925 Gold.
 * +2% of max Health in Attack Damage (Unique). +45 Armor, +18% Critical Strike Chance. 2405 Gold.
 * +45 Attack Damage. 1650 Gold.
 * +35 Attack Damage. +15% Life Steal, UNIQUE Active: Deals 150 magic damage and slows the target champion by 50% for 3 seconds (400 range). 60 second cooldown. 1825 Gold.
 * +10 Attack Damage. +100 Health, +3% Lifesteal. 475 Gold.
 * +20 Attack Damage. +700 Health, UNIQUE Passive: Physical attacks reduce your target's Movement Speed for 2.5 seconds. 3250 Gold.
 * +35 Attack Damage. +45 AP, Passive: On attack/spellcast, increases your Attack Speed by 4% and Ability Power by 6. Lasts 5 seconds (stacks up to 8 times). 2235 Gold.
 * +35 Attack Damage. +35 Magic Resistance, UNIQUE Passive: If you would take Magic Damage which would leave you at less than 30% of your Maximum Health, you first gain a shield which absorbs 300 Magic Damage for 4 seconds. 45 second cooldown. 1800 Gold.
 * +60 Attack Damage. +75 AP, +20% Life Steal, +25% Spell Vamp, UNIQUE Active: Deals 300 magic damage and slows the target champion by 50% for 3 seconds (700 range). 60 second cooldown. 3625 Gold.
 * +80 Attack Damage. +25% Critical Strike Chance, UNIQUE Passive: Critical hits now deal 250% damage instead of 200%. 3830 Gold.
 * 40% Armor Penetration (Unique). +40 Attack Damage 2290 Gold.
 * +10 Attack Damage. 415 Gold.
 * +30 Attack Damage. +40% Attack Speed, +25 Armor, UNIQUE Passive: On hit, deals Magic Damage equal to 4% of the target's maximum Health.(maximum 120 Magic Damage against monsters) 3800 Gold.
 * +15 Attack Damage. +23 Armor, UNIQUE Passive: 15% chance on attack to deal 500 damage to a minion. 1000 Gold.
 * +20 Attack Damage. +7 Mana Reger/5 sec, +350 Mana, UNIQUE Passive:2% of your max Mana is converted to Attack Damage, UNIQUE Passive: Each time you attack, you gain one maximum mana (3 second cooldown). Each time you use an ability, you gain four maximum mana (3 second cooldown}. Bonus caps at 1000 mana. 2110 Gold.
 * +25 Attack Damage. 975 Gold.
 * +18 Attack Damage. +225 Health, Passive: 25% chance on hit to reduce your target's Movement Speed by 30% for 2.5 seconds. 1315 Gold.
 * +10 Attack Damage. UNIQUE Passive: Your champion gains +5 damage per stack, receiving 2 stacks for a kill or 1 stack for an assist. This effect can stack 20 times; you lose a third of your stacks if you die. At 20 stacks, your champion's movement speed is increased 15%. 1369 Gold.
 * +55 Attack Damage. +30% Attack Speed. UNIQUE Passive: Physical attacks reduce your target's Armor by 15 for 5 seconds, (maximum 3 stacks). 3065 Gold.
 * +60 Attack Damage. +15% Lifesteal, Passive: Gain an additional 1 Physical Damage and 0.25% Lifesteal per kill. Maximum of +40 Attack Damage and 10% Lifesteal. Bonuses are lost upon death. 3200 Gold.
 * +25 Attack Damage. UNIQUE Passive: Reduces ability cooldowns by 10%, +15 Armor Penetration. 1337 Gold.
 * +50 Attack Damage. +15 Health Regen per 5 sec, +5 Mana Regen per 5 sec, Passive: Your attacks Splash, dealing Physical Damage in a small area around the target. 2070 Gold.
 * +30 Attack Damage. +30 AP, +30% Attack Speed, +15% Crit Chance, +12% Move Speed, +250 Health, +250 Mana, UNIQUE Passive: 25% chance on hit to slow the target by 35% for 2.5 seconds; on cast, increases your base Attack Damage by 150% for one attack. 4070 Gold.
 * +23 Attack Damage. +30 Armor, +18% Life Steal, UNIQUE Passive: 20% chance on attack to deal 500 magic damage to a minion, UNIQUE Active: Places an invisible ward with 1100 range sight and lasts for 3 minutes. 3 minute cooldown. 1600 Gold.
 * +30 Attack Damage. +15% Critical Chance, UNIQUE Passive: +20 Armor Penetration 15% Cooldown Reduction, Unique Active: You gain +20% movespeed and +50% attack speed for 4 seconds, Attacking enemy units with melee attacks increases the duration by 2 to a maximum of 8 seconds. 60 second cooldown. 2687 Gold.

Consumable

 * : +10 Attack Damage and +140-235 health, based on champion level, for 4 minutes. 250 Gold.

Champion Abilities

 * increases his attack damage by 60/75/90 for 6/7/8 seconds.
 * increases his attack damage by 40/55/70/85/100 + 0.4/0.55/0.7/0.85/1 per 1% health he is missing for 5 seconds.
 * passively increases his attack damage by 8/10/12/14/16. He can also activate this ability to increase his attack damage by 20/28/36/44/52 instead, also increasing nearby allied champions' attack damage by half that amount.
 * increases his attack damage by 30/40/50/60/70 for 20 seconds.
 * increases an allied unit's attack damage by 14/23/32/41/50 for 5 seconds.
 * increases her attack damage by 15% of her ability power.
 * increases her attack damage by 4/10/16/22/28 (+0.3 per AP) for 10 seconds.
 * increases his attack damage by 20/25/30/35/40% for 6 seconds.
 * passively increases his attack damage by 15/20/25/30/35 and doubles that bonus for 10 seconds on activate.
 * gives him 20/30/40/50/60 attack damage as long as he is in the trail.
 * increases his attack damage by 7/14/21/28/35 + 1% of his max health for 6 seconds.
 * increases her attack damage by 1.5/2/2.5/3/3.5 when she is hit by an attack or hits an enemy for 5 seconds (stackable up to 10 times). She can activate this ability to gain max stacks for 5 seconds.
 * increases his attack damage by 25% of his armor.
 * increases his attack damage by 25/35/45/55/65.
 * increases the attack damage of nearby allied champions by 8/11/14/17/20.
 * increases his attack damage by 30/60/90 and half of that to nearby allied champions.
 * increases his attack damage by 20/25/30/35/40 for 8 seconds.
 * increases his attack damage by 5 when he kills a unit or critically strikes for 15 seconds (stackable up to 8 times).
 * increases his attack damage by 15/25/35 for 5/6/7 attacks or 12 seconds.
 * increases his attack damage by 8/12/16/20/24.
 * increases his next three strikes by 15/30/45/60/75 attack damage.

Masteries

 * increases your champion's attack damage by 1/2/3.

Summoner Spells

 * summons a beacon that increases nearby allied unit's attack damage by 10-35 for 15 seconds (20 seconds with ).

Runes

 * Strength and Might runes increase attack damage.

Neutral Buffs

 * The buff gives 40 attack damage for 8 minutes.

Champion Attack Damage Rankings
†  increases his attack damage by 25% of his armor. This includes his base armor and is a passive ability thus essentially increasing his base damage unlike all other summoner abilities which are temporary or situational boosts to damage. The increase to his damage is 6 at level 1 and 22 at level 18, this is incorporated into the numbers above.

‡  increases his attack damage by 8/10/12/14/16. This is a ranked ability and thus could not be counted on for a bonus at level 1. However, arguments could be made that at level 18 you will have 5 ranks and thus this will increase he damage permanently by 16. This would put basic attack at 124 damage, surpassing  for third place. Since it is not a guaranteed bonus like he is not included in the top 5 list. The same is true for, who can have always active her bonus damage, giving her a total of 126 damage at level 18.