gpt-6POST

Beyond public models: how far ahead OpenAI and Anthropic internal models are

The author compares Opus 5.5, Fable 5.1 and GPT-6 Astra, and estimates that both companies' internal models are roughly two months ahead of their public versions.

Haider.

@haider1Archived 2026.09.24Originally posted 2026.09.24

Haider. @haider1Originally posted 2026.09.24

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opus 5.5, fable 5.1, and gpt-6 astra — and we're only comparing the public models here both openai and anthropic have more advanced internal models. oai showed internal-model performance graphs around the navier-stokes work, which could give us a rough idea of how far ahead they are internally probably around 2 months ahead?

x.com/haider1/status/2102793866067972110Archived 2026.09.24 10:16