LoL Item Builder

How to Use the LoL Item Builder

Pick a champion and a level, fill the six item slots and choose your rune shards: the stat sheet updates as you build. It covers all 173 champions and 204 items on patch 16.20.

1. Choose the champion and move the level slider from 1 to 18.
2. Click an item slot and pick an item; filter by tier, stat or map, or search by name.
3. Choose one stat shard per row.
4. Switch to Build B to make a second build; the stat sheet shows both and the difference.
5. Copy the link to share the build: it opens with the same champion, level, items and shards.

How Champion Stats Grow per Level

A champion's stat at level n is the base value plus the growth per level times (n - 1) × (0.7025 + 0.0175 × (n - 1)). The growth is slower at low levels and faster at high ones, and the total from level 1 to 18 is exactly 17 times the growth per level.

stat(n) = base + growth × (n - 1) × (0.7025 + 0.0175 × (n - 1))

Example: Jinx has 630 health and 59 attack damage at level 1, and 2,415 health and 114 attack damage at level 18, before items. The calculator reads every champion's base stats and growth from the game's data files, because the per-level attack damage in Riot's Data Dragon is not reliable on recent patches.

How Armor and Magic Resist Reduce Damage

A champion with positive armor takes physical damage multiplied by 100 / (100 + armor); magic resist does the same for magic damage. 100 armor halves physical damage, 200 armor cuts it by two thirds.

damage taken = damage × 100 / (100 + armor)
effective health = health × (1 + armor / 100)

That is why the calculator shows effective health: the raw damage needed to kill the champion. 2,000 health with 100 armor takes 4,000 physical damage to kill.

Lethality, Armor Penetration and the Order They Apply

Against armor, the game applies flat armor reduction first, then percentage armor reduction, then percentage armor penetration, then lethality. Lethality is flat armor penetration; magic penetration works the same way against magic resist.

1. Flat armor reduction (can take armor below zero).
2. Percentage armor reduction.
3. Percentage armor penetration (items such as Last Whisper and its upgrades).
4. Lethality, the flat penetration from assassin items.

Penetration never takes the target's armor below zero; reduction can. The calculator lists your lethality, armor penetration and magic penetration with the other stats.

Ability Haste and Cooldown Reduction

Cooldown reduction from ability haste is AH / (AH + 100): 100 ability haste cuts cooldowns by 50%. Each point is worth the same, so there is no cap and no falloff in how many casts it adds.

cooldown reduction = ability haste / (ability haste + 100)

The stat sheet shows both numbers: your ability haste and the cooldown reduction it gives.

Attack Speed and Its Cap

Attack speed is the champion's base attack speed plus its attack speed ratio times all bonus attack speed; since patch 25.S1.3 it is capped at 3.003 attacks per second for most champions. The cap was 2.5 before.

attack speed = base + ratio × bonus attack speed %

Bonus attack speed comes from items, the attack speed shard and levels. A few champions have their own cap or ignore it with their kit, which the calculator does not count.

Gold Efficiency: What Each Stat Is Worth

Gold efficiency compares an item's stats, priced at what the cheapest basic items charge for them, with the item's cost. On patch 16.20 one point of attack damage is worth 35 gold and one point of ability power 20 gold.

Passives and actives are not priced, so most finished items come out under 100%: what they lose there they make up with their effects. The LoL items page lists the gold efficiency of every item.

What the Calculator Counts

• Counted: base stats and level growth, item stats, rune stat shards, adaptive force, the attack speed cap and the move speed soft caps.
• Not counted: item passives and actives, stacking items and runes, keystones, champion abilities and passives, and buffs from objectives or the fountain.

So your stats in a game can be higher than the sheet: a fully stacked item or a champion passive adds on top. Adaptive force turns into ability power when the build has more bonus ability power than bonus attack damage, and into attack damage otherwise (9 adaptive force is 9 AP or 5.4 AD).

Frequently Asked Questions

What is a LoL item builder?

A calculator that shows a champion's stats with the items, level and rune shards you choose, before you play the build.

Is the item builder updated for the current patch?

Yes. It reads the game data of the current patch (16.20) and checks for a new patch every hour.

How do I share my build?

Press Copy link. The link opens the builder with the same champion, level, items and shards, and build B if you made one.

How much damage does armor block?

A champion with A armor takes 100 / (100 + A) of physical damage: 100 armor blocks half, 200 armor two thirds.

How does lethality work?

Lethality is flat armor penetration. It applies after armor reduction and percentage armor penetration, and cannot take armor below zero.

How much cooldown reduction is 100 ability haste?

50%. Cooldown reduction is ability haste / (ability haste + 100).

What is the attack speed cap?

3.003 attacks per second for most champions since patch 25.S1.3. It was 2.5 before.

What is gold efficiency?

The gold value of an item's stats divided by its cost. Each stat is priced at what the cheapest basic item charges for it, such as 35 gold per attack damage.

Does it work for ARAM?

Yes. Switch the item list to ARAM to see the items of the ARAM shop.

Why don't my stats match the game?

The calculator does not count item passives, stacks, keystones or champion abilities, which can add stats in a game.