// Rulebook v1

The rules

As adopted by the rating system, which adopted them itself.

01Purpose

The elo rating expresses, as a single number, where a person's competitive results stand relative to other rated persons. It is not a measure of worth. It is a measure of standing on this list.

02The rating

Each credential is converted to a percentile within its own population (for example, all rated Chess.com blitz players, or all SAT takers), and from there to a standard score z.

Only the strongest credential in each field counts. Fields are ranked, and the rating is:

rating = 1200 + 300 × (z₁ + 0.5·z₂ + 0.25·z₃)

Exceptional strength in one field is worth more than moderate strength in several, and a second or third field only ever adds.

03Verification

Class	Weight	Cap
Verified (platform API, ownership proven)	100%	z 4.5
Proof (linked evidence, reviewed)	80%	z 3.5
Self-reported	50%	z 1.5

Proof links count as self-reported until reviewed. Ratings of 2000 and above (Expert and up) require at least one verified platform account. A platform account may be linked to one profile only. Misrepresentation results in removal from the list.

04Updates

Ratings change only when credentials change: a new verified account, a refreshed platform rating, a new score or rankvement. Nothing anyone else does can lower your rating.

05Titles

Each title holds a set share of the ladder. Titles are assigned by rating, from the top: the highest-rated 0.1% are Grandmaster, and so on down. The highest-rated person is always Grandmaster, and tied ratings share a title. As the ladder grows, cutoffs move, so a title can change while the rating stays the same.

★	Grandmaster	0.1%
LG	Legend	0.4%
MS	Master	1.5%
EL	Elite	3%
EX	Expert	5%
D	Diamond	10%
P	Platinum	15%
G	Gold	20%
S	Silver	25%
B	Bronze	20%

06Eligibility

The list is open to persons aged 18 and older. Every person on it chose to be there and can leave at any time.

07Finality

All decisions of the rating system are final, until your next result.