Changes

May 2026

2026-05-20

• added gemini-3.5-flash
• updated elo formula

2026-05-15

• added chessbench.ai/changes

2026-05-11

• officially announced chessbench.ai

2026-05-07

• added:
  • gpt-5
  • gpt-5-mini
  • gpt-5-nano

2026-05-02

• added:
  • o3
  • o3-mini
  • o4-mini

2026-05-01

• added claude-opus-4-7

April 2026

2026-04-30

• added:
  • claude-sonnet-4-6
  • claude-opus-4-6
  • gpt-4.1-mini
  • gpt-4.1-nano

2026-04-28

• added:
  • gpt-4o-2024-05-13
  • gpt-4o-2024-08-06
  • gpt-4o-2024-11-20

2026-04-27

• added chessbench.ai/timeline

2026-04-26

• added chessbench.ai/leaderboard
• added:
  • gpt-3.5-turbo-0125
  • gpt-4-0613
  • gpt-4-turbo-2024-04-09

2026-04-21

• added:
  • gemini-3.1-flash-lite-preview
  • claude-opus-4-1-20250805
  • claude-haiku-4-5-20251001
  • claude-sonnet-4-5-20250929
  • claude-opus-4-5-20251101

2026-04-19

• silently launched chessbench.ai in preview mode, with the following models:
  • gemini-2.0-flash
  • gemini-2.0-flash-lite
  • gemini-2.5-flash
  • gemini-2.5-flash-lite
  • gemini-2.5-pro
  • gemini-3-flash-preview
  • claude-sonnet-4-20250514
  • claude-opus-4-20250514