Rumored benchmarks show Claude Sonnet 5.5 crushing GPT-6 sol

On September 29, multiple third-party sources simultaneously leaked claims that Anthropic's Claude Sonnet 5.5 significantly outperforms OpenAI's GPT-6 sol in benchmarks, sparking community debate about OpenAI's competitiveness. All figures currently come from unofficial channels and have not been confirmed by either party.

Confirmed

• X user ns123abc (84K followers) posted screenshots claiming GPT-6 sol was soundly beaten by Claude Sonnet 5.5 in comparisons (their words: "brutally mogged").
• LuminaBench leaked that Claude Sonnet 5.5 scored 56 on the Artificial Analysis Intelligence Index, versus 48 for the competing model Sol.
• Another user claims Sonnet 5.5 scored 56 on the Intelligence Index—second only to Claude Opus 5.5 and above GPT-6 Astra.
• The account AIScreening posted third-party test screenshots showing Sonnet 5.5 well ahead of GPT-6 sol and very close to GPT-6 Astra.
• Another quoted post says Claude Sonnet 5.5 Max ranks second on the leaderboard, above GPT-6 Astra Max and just slightly below Opus-5.5; commenters see OpenAI as being in trouble.

Unconfirmed

• All benchmark scores and rankings come from leaks and third-party reposts; test baselines, specific questions, and version details are unclear, with no official confirmation from Anthropic, OpenAI, or Artificial Analysis.
• Full details of m1's evaluation methodology and source screenshots have not been disclosed.

Why it matters

• If the leaks hold up, it means Anthropic's mid-tier Sonnet 5.5 could suppress OpenAI's GPT-6 sol and close in on GPT-6 Astra—directly affecting user choices and market narratives between the two vendors.
• Multiple independent accounts spreading similar conclusions on the same day suggests that, even if the numbers are imprecise, community anxiety over the declining relative standing of OpenAI's frontier models is intensifying.

2026-09-29 ~ 2026-09-29 · 5 related posts

Full story(3 episodes)→

• Episode 1: Rumored benchmarks show Claude Sonnet 5.5 crushing GPT-6 sol(2026-09-29, 5 posts)
• Episode 2: Sonnet 5.5 Nearly Matches Opus 5.5 but Sets Token Consumption Record(2026-09-29, 12 posts)
• Episode 3: Every's Hands-on: Claude Sonnet 5.5 Is 30% Faster, Cheaper, and Matches Opus in Writing(2026-09-29, 6 posts)

• Claude Sonnet 5.5 Reportedly Scores 56 on Artificial Analysis Intelligence Index — thesaraharminta · 2026-09-29
• [source] Leak claims OpenAI GPT-6 sol brutally outclassed by Claude Sonnet 5.5 — ns123abc · 2026-09-29
• [source] Leaked benchmarks claim Claude Sonnet 5.5 hits 56 on AA index, beating Opus 5.5 — airesearch12 · 2026-09-29
• [source] Claude Sonnet 5.5 Max Reportedly Ranks Second on AI Index, Above GPT-6, Near Opus-5.5 — airesearch12 · 2026-09-29
• Third-party benchmark shows Claude Sonnet 5.5 crushing GPT-6 sol, nearly matching GPT-6 Astra — rickasaurus · 2026-09-29