What Is a Chess Problem and How Can You Find Them in a Free Database?

Updated

A chess problem is a composed position with a stipulated goal — most often "mate in n" — that has a unique solution and is designed to show a specific idea rather than to arise from a real game. You can find and search over 256,000 of them in the MESON Chess Problem Database, which its creator Brian Stephenson states has been free and online since 2006. This article explains how problems differ from puzzles and endgame studies, how to read problem notation, and how to search MESON by composer, stipulation, or theme.

Chess problem vs. puzzle vs. endgame study

These three terms get used loosely, but they describe different things:

| Type | Origin | Typical stipulation | What it tests | |---|---|---|---|---| | Chess problem | Composed | "Mate in n" (usually 2–4) | Whether you can find the one intended key and its variations | | Practical puzzle | Taken from a real game | "White to play and win" | Tactical calculation in a game-like setting | | Endgame study | Composed | "White to play and win/draw" | Precise endgame technique and resourcefulness |

The key distinction is composition. A problem is built backwards from the idea the composer wants to show, so the position may look artificial — pieces placed where no game would leave them. That artificiality is the point: it isolates the theme.

The BDS Website, home of MESON, also hosts Stephenson's own compositions and his endgame study articles, so you can see both categories side by side.

How to read problem notation

A problem diagram is accompanied by a short caption. The two things you need to parse are the stipulation and the side to move.

  • Stipulation — the goal and move count, e.g. #2 (mate in 2), #3 (mate in 3), + or Win (White to play and win), = or Draw.
  • Side to move — if not stated, the convention is White to move. Some sources print "Black to move" explicitly when it differs.
  • Solution notation — moves are given in standard algebraic form, with the key move listed first, followed by Black's defenses and White's replies.

For example, a #2 caption means: White moves, Black replies, White mates on the second move. The first White move is the key.

What to look for when solving

Three concepts come up repeatedly in problem literature:

  • Key move — the unique first move that makes the stipulation work. It often looks counterintuitive, and finding it is the main challenge.
  • Tries — plausible first moves that fail to a single Black defense. Composers build these in deliberately to mislead solvers.
  • Thematic variations — the lines that demonstrate the problem's idea (e.g. a pin, a switchback, a Grimshaw interference). These are what the composer actually wanted to show.

If you only find the key, you have solved the problem; if you can also identify why the tries fail, you have understood it.

Searching MESON

MESON is the Meson Chess Problem Database, accessible from the BDS Website menu. According to the site, it contains more than 256,000 items and has been free and online since 2006. Typical search dimensions for a problem database of this kind include:

  • Composer — find all problems by a given author.
  • Stipulation — filter to #2, #3, studies, and so on.
  • Theme or keyword — locate problems illustrating a specific idea.
  • Source — problems published in a particular magazine or tournament.

The exact query fields and result layout are best confirmed on the database itself, since the interface is maintained by the site owner and may change.

Related resources on the same site

Beyond MESON, the BDS Website links to:

  • Chess Problems — Stephenson's own compositions, which he notes are still being added gradually.
  • Endgame Studies — his articles on studies, written for Chess since 2006 and, with Roland Ott, for Schweizerische Schachzeitung since 2014.
  • BDS Ladder — a solving competition that ran for a short time and is now closed, though the problems used remain available to try.

If your interest is solving rather than composing, the Ladder archive is a ready-made set of positions to work through. If your interest is the literature, the endgame study articles give a running commentary on the field.