Carlsen number for every Lichess user

ChessSoftware DevelopmentLichess
Find out if you (indirectly) beat the current World Champion

TLDR: go to website, enter your Lichess username and find out if you beat someone who beat someone who ... who beat DrNykterstein a.k.a Magnus Carlsen. For example here is the WC# for german11, the Lichess player with most games:

What is a WC#

World Chess Champion Number or WC# is a number defined for every Lichess player. The current World Champion gets WC#0, everyone who won a game against him on Lichess gets WC#1, everyone who won a game against someone with WC#1 gets WC#2 and so on. In other words your WC# is a length of a shortest chain of players between you and the World Champion where each player won a game against the next one. The lower your number the better.

The idea of counting distances came from the Erdős number. It's a similar metric for math paper coauthorship. There are many other similar numbers, e.g. Bacon number for Hollywood actors and Morphy number for chess players. There is also a website that does exactly the same, but for FIDE OTB tournament games only.

What should I do to get a WC#

Most probably winning a single blitz/rapid/classical rated game on Lichess is enough! Chess is not a game where the stronger player has 100% winrate against the weaker one. Magnus Carlsen is considered to be the strongest player but at the moment of writing he has 86 blitz defeats. Players that beat him will lose to someone weaker, then weaker players lose to someone even weaker until eventually every single regular Lichess player has WC#. This works similar to the Six degrees of separation concept.

How to read the website

Results page

Every column is a chain of games, starting with selected player and ending with DrNykterstein. The leftmost column is the current state, other columns are the WC# history in reverse chronological order. Clicking on the game will redirect you to the page of that game so you could verify that the chain actually exist.

What are the exact rules

  1. All Lichess games are processed in chronological order. To get WC#n you have to beat someone who already got WC#n-1. People tend to play stronger over time, it's unfair to reward someone with WC#n for beating person before they reached WC#n-1. As a bonus that means that your WC# improves only as a result of you winning a game, it doesn't happen because some of your former opponents got better.
  2. Only rated games. People usually don't play seriously in unrated games.
  3. Only blitz/rapid/classical time control. I experimented with adding bullet games, but it's not uncommon in Bullet to beat someone with 1000 elo higher rated player, that caused almost everyone to have WC#3 or lower. Not very interesting.
  4. Only games with at least 10 moves. There are lots of resigns on ~4th move, not very informative.
  5. Games where cheats were detected are excluded when possible.