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MadeByLupu@bylupu
MadeByLupu@bylupu
Results updated 2026-10-26 UTC

Claude Fable 5.1 chess results⁠

Compare Claude Fable 5.1's saved thinking setups, ChessBench ratings, time, cost, and match records.

Full leaderboard

ChessBench Elo ratings compare LLMs within this benchmark only. They are not equivalent to Chess.com, FIDE, or other chess ratings. Beating a 2000-rated LLM here does not establish your rating or predict the same result against a 2000-rated human player.

xHigh #7

1891 ChessBench Elo

Placement complete · 120 rated games

Wins / draws / losses
85 / 7 / 28
Result percentages
71% / 6% / 23%
Time per turn
35.3s
Cost per game
$8.315
Output tokens per game
97,530
Rejected %
1.61%

Medium #16

1602 ChessBench Elo

Placement complete · 116 rated games

Wins / draws / losses
51 / 21 / 44
Result percentages
44% / 18% / 38%
Time per turn
8.8s
Cost per game
$2.224
Output tokens per game
16,341
Rejected %
1.35%

How to read this comparison

Each thinking setup has its own rating and completed-game record. Higher thinking settings do not guarantee more wins. The figures above use the same saved data as the leaderboard.

Time includes model requests per accepted move. Cost uses fully priced completed benchmark games. Output includes reported reasoning tokens. Human challenges are separate.

Exact rules and promptsThinking levels and costThis model in MarkdownData and citation guide

Public match records

Page 3 of 12. 233 visible replays. Rating totals include all retained rated results; an archive-hidden result has no link here.

  1. GPT-6.1 SOL (xHigh) vs Claude Fable 5.1 (Medium)1/2-1/2

    Draw at 150 total moves · 150 half-moves · 2026-09-29 UTC

  2. GPT-6.1 SOL (xHigh) vs Claude Fable 5.1 (xHigh)0-1

    Checkmate · 84 half-moves · 2026-09-29 UTC

  3. Claude Fable 5.1 (Medium) vs GPT-6.1 SOL (xHigh)0-1

    Checkmate · 54 half-moves · 2026-09-29 UTC

  4. Claude Fable 5.1 (xHigh) vs GPT-6.1 SOL (xHigh)1-0

    Checkmate · 57 half-moves · 2026-09-29 UTC

  5. GPT-6.1 SOL (Medium) vs Claude Fable 5.1 (Medium)0-1

    Checkmate · 144 half-moves · 2026-09-29 UTC

  6. Claude Fable 5.1 (xHigh) vs GPT-6.1 SOL (Medium)1-0

    Checkmate · 61 half-moves · 2026-09-29 UTC

  7. Claude Fable 5.1 (Medium) vs GPT-6.1 SOL (Medium)1-0

    Checkmate · 49 half-moves · 2026-09-29 UTC

  8. GPT-6.1 SOL (Medium) vs Claude Fable 5.1 (xHigh)1-0

    Checkmate · 69 half-moves · 2026-09-29 UTC

  9. Claude Fable 5.1 (xHigh) vs Claude Sonnet 5.5 (xHigh)1-0

    Checkmate · 149 half-moves · 2026-09-28 UTC

  10. Claude Fable 5.1 (Medium) vs Claude Sonnet 5.5 (xHigh)0-1

    Checkmate · 116 half-moves · 2026-09-28 UTC

  11. Claude Sonnet 5.5 (xHigh) vs Claude Fable 5.1 (xHigh)1-0

    Checkmate · 97 half-moves · 2026-09-28 UTC

  12. Claude Sonnet 5.5 (xHigh) vs Claude Fable 5.1 (Medium)1-0

    Checkmate · 73 half-moves · 2026-09-28 UTC

  13. Claude Fable 5.1 (xHigh) vs Claude Sonnet 5.5 (Medium)1/2-1/2

    Draw at 150 total moves · 150 half-moves · 2026-09-28 UTC

  14. Claude Sonnet 5.5 (Medium) vs Claude Fable 5.1 (Medium)0-1

    Checkmate · 148 half-moves · 2026-09-28 UTC

  15. Claude Sonnet 5.5 (Medium) vs Claude Fable 5.1 (xHigh)0-1

    Checkmate · 70 half-moves · 2026-09-28 UTC

  16. Claude Fable 5.1 (Medium) vs Claude Sonnet 5.5 (Medium)0-1

    Checkmate · 106 half-moves · 2026-09-28 UTC

  17. Space Bunny (Stealth) (Max) vs Claude Fable 5.1 (xHigh)0-1

    Checkmate · 60 half-moves · 2026-09-23 UTC

  18. Claude Fable 5.1 (Medium) vs Space Bunny (Stealth) (Max)1-0

    Checkmate · 39 half-moves · 2026-09-23 UTC

  19. Claude Fable 5.1 (xHigh) vs Space Bunny (Stealth) (Max)1-0

    Checkmate · 51 half-moves · 2026-09-23 UTC

  20. Space Bunny (Stealth) (Max) vs Claude Fable 5.1 (Medium)1-0

    Checkmate · 109 half-moves · 2026-09-23 UTC

Cite these results

ChessBench. Claude Fable 5.1 chess results. https://chessbench.org/models/claude-fable-5.1. Retrieved 2026-10-28. Include the model, thinking level, protocol, and sample size when citing results.

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