# Coachless

> League of Legends analytics that rank champion builds, items, runes and summoner spells by Win Probability Added (WPA), meaning how much a choice changes the chance of winning, instead of by raw win rate. Computed from real ranked games (Emerald and above). Built and run by xPetu.

The site is a client-rendered web app; the pages below carry their data in the rendered HTML, not in this file. Every champion has one page per section, e.g. https://coachless.gg/builds/ahri, https://coachless.gg/items/ahri/legendaries, https://coachless.gg/runes/tree/ahri/precision/domination and https://coachless.gg/spells/ahri. The champion name in the URL is lowercase with spaces and punctuation removed (kaisa, drmundo, ksante, nunu).

## Method

- [What is WPA?](https://coachless.gg/wpa): why item and rune win rates are biased by who buys them and when, plus how WPA removes that bias by subtracting the win probability a player already had before the decision.

## Data pages

- [Builds](https://coachless.gg/builds/all): per champion, every keystone, summoner spell, starting item, boots and legendary item ranked by WPA, with pick counts.
- [Items](https://coachless.gg/items/all/legendaries): every item with win rate, pick rate and WPA, filterable by champion and purchase slot.
- [Runes](https://coachless.gg/runes/tree/all/precision/domination): keystones, rune trees and shards ranked by WPA per champion.
- [Summoner spells](https://coachless.gg/spells/all): summoner spell performance per champion.
- [Sitemap](https://coachless.gg/sitemap.xml): all champion pages.

## About

- [Premium](https://coachless.gg/premium): multi-patch filtering, matchup filtering, saved builds and the review tool.
- [Terms of Service](https://coachless.gg/terms-of-service)
- [Privacy Policy](https://coachless.gg/privacy-policy)

## Optional

- [Coachless on X](https://x.com/CoachlessGG)
- [Discord](https://discord.com/invite/KNCknuK9uX)