How many legal checkmate positions are there?

This page summarizes the projects mentioned and recommended in the original post on /r/chess

Our great sponsors
  • WorkOS - The modern identity platform for B2B SaaS
  • InfluxDB - Power Real-Time Data Analytics at Scale
  • SaaSHub - Software Alternatives and Reviews
  • ChessPositionRanking

    Software suite for ranking chess positions and accurately estimating the number of legal chess positions

    Taking "a sample of random legal positions" is nowhere near as trivial as you make it sound. You can have a position that "looks" legal (as in: at most one King is in check, there are no impossible multiple checks, the Kings are not adjacent, the "correct" side is to move, etc., etc.) but are not legal. As in, they couldn't have been reached through any legal sequence of moves from the starting position. Then there's also the question of: does that actually matter? What if the position is reachable only in 960? How would discarding such positions contribute to solving "chess"? And so on...

  • WorkOS

    The modern identity platform for B2B SaaS. The APIs are flexible and easy-to-use, supporting authentication, user identity, and complex enterprise features like SSO and SCIM provisioning.

NOTE: The number of mentions on this list indicates mentions on common posts plus user suggested alternatives. Hence, a higher number means a more popular project.

Suggest a related project

Related posts