The overall score is not a simple average but a weighted blend of three parts: (w_P·P + w_T·T + v·R) / (w_P + w_T + v). Each part's weight is expressed in “virtual votes”: the more evidence, the more weight.
P · Site scores: scores from AniList, MyAnimeList, Bangumi, bilibili and other sites are first calibrated to one scale using titles rated on both sites (every site scores differently), then weighted by site reliability × votes into a consensus. With few votes it shrinks toward the season baseline, so an obscure high score cannot jump straight to #1 (and a thin score below the baseline is not pulled up). Sites with fewer than 100 votes are ignored.
T · Fan sentiment: public reviews and comments on each site are rated one by one by a local AI model as very positive / positive / mixed / negative / very negative. The sentiment score shown on pages shrinks toward a neutral 6 (a handful of comments cannot inflate it); the overall score uses the unshrunk average, first adjusted for each site's commenting habits, then calibrated against the sentiment of comparable titles. It counts from 10 comments, and its weight grows with the number of comments up to 35% of the total. Only the latest ~40 comments per site are read (plus ~50 posts from each forum's episode threads, which weigh less and together count for at most 30%): a sample, not everything. Pages show only spoiler-free excerpts of up to 140 characters, linked to the original.
R · Community: ratings by AniRanking users, one vote per person.
To be ranked, a title needs at least 1,000 votes behind its site scores, or at least 30 analyzed comments (plus a site score), or at least 20 AniRanking ratings. Only aired, non-adult TV / TV short / ONA titles are ranked; Movie, OVA, Special, Music video, and single-episode ONA / TV releases (web films, specials, music videos, promos) are not. Titles without enough evidence stay off the chart; the season chart lists them under “Waiting for more ratings”. Scores with little behind them are marked “Small sample” (fewer than 30 AniRanking ratings and too few site votes and comments). Rank arrows compare with the chart from about 7 days earlier.