Tactics and pattern recognition

• ChessTempo — rated puzzles that calibrate to your blind spots. Best free tactics trainer on the internet.
• chess.com Puzzles — daily puzzles + Puzzle Rush; integrated with your chess.com profile.
• Lichess Training — free, deep set, includes puzzle streak.

Endgame study

• Silman’s Complete Endgame Course — graded by rating band; the canonical endgame textbook for adult improvers.
• Lichess Practice — interactive endgame drills, free.
• De la Villa, 100 Endgames You Must Know — the harder follow-up to Silman.

Opening repertoires

• Chessable — spaced-repetition opening trainers. Best paid tool for fixing opening leaks.
• Lichess studies — find an existing repertoire study at your rating band, fork it, edit.
• “Keep It Simple” series (Christof Sielecki) — solid main-line repertoires for both colors.

Strategy and middlegame

• Silman, How to Reassess Your Chess — the imbalances framework.
• Aagaard, Positional Play — harder, three-question framework.
• Karpov, Move by Move (Mihail Marin) — the canonical Drifter-fix book.

Defense and resilience

• Soltis, The Art of Defense in Chess.
• Karpov games on chess24 / chess.com — search “Karpov defends” for instructive examples.

Streaming and learning content

• Daniel Naroditsky’s speedrun series — best instructional content on YouTube for sub-1800 players.
• John Bartholomew’s Chess Fundamentals series.
• Hanging Pawns — opening reviews calibrated for club players.

Disclosure: external book and platform recommendations are unaffiliated unless explicitly noted. We update this list quarterly.