Formula

Eligibility

1. Current tier ≥ Master in Ranked Solo/Duo (latest ladder snapshot), or any tier if the Riot ID was added to the tracking list on the home page.
2. Exactly the 30 most recent qualified games on this champion in the current split.
3. Qualified game = Ranked Solo/Duo, not a remake, ended in the last 90 days.
4. No win-rate requirement. Sub-50% win rate is still ranked.

Score

absLP is absolute LP (Master, Grandmaster and Challenger share one LP pool). p̂₃₀ is the win rate over exactly the last 30 qualified games. With K = 600, win rate can move a player at most ±300 points, typically ±60: rank dominates, win rate breaks ties. Players below Master use converted LP: each division below Master subtracts 100 (Diamond I = LP − 100, Diamond IV = LP − 400, Emerald I = LP − 500), so a large win-rate gap can lift Gold II above Gold I, but not across several divisions.

Why a fixed 30-game window

Everyone has the same sample size, so two win rates compare directly with no Bayesian shrinkage or confidence factor. The cost: the standard error of a 30-game win rate is 9.1 percentage points, or ±55 Score for ±1 SD. Enough to break ties, not enough to reverse a real rank gap.

Running parameters

Known limitations

• Master+ only (about 0.1% of players). Diamond players will not find themselves here.
• A 30-game window carries ±9.1 pp of noise. That is the price of measuring current form instead of a whole season.
• Game difficulty is not measured. Carrying and being carried both count as one win.
• No per-role split yet. The same champion played mid and top shares one table.
• The Riot API returns at most 10,000 Master players. On servers with a larger Master tier (VN), the lowest-LP Masters cannot be ranked.
• Data refreshes once a day, not in real time.

Data source & privacy

Data comes from the Riot Games API (league-v4, match-v5). Only the current Riot ID is stored and displayed; no name history. There is no live-game lookup.