OpenAI Codex changelog

Every change to OpenAI Codex that Modelpeers has recorded, newest first, each with the source it came from. The record starts Oct 6, 2025.

All (36)Releases (13)Retiring (7)Breaking changes (2)Prices/limits (7)Quality (5)Benchmarks (2)

October 2026

GPT-6.1 Sol and OpenAI Codex

2 products from OpenAI

Benchmark3w

GPT-6.1 Sol in Codex matches Astra at 58.2% on Terminal-Bench 4.0 for about a fifth of the cost

Codex with GPT-6.1 Sol at max effort resolved 58.18% (plus or minus 3.1, 330 trials) for $634.24 total, against $3,267.18 for GPT-6 Astra at the same score. Posted October 6, 2026.

Who is affected:: Codex users deciding between GPT-6.1 Sol and GPT-6 Astra.
What to do:: Try GPT-6.1 Sol first for terminal tasks.

September 2026

GPT-6 Astra and OpenAI Codex

2 products from OpenAI

BenchmarkSep 3, 2026

GPT-6 Astra in Codex scores 58.2% on Terminal-Bench 4.0

Codex with GPT-6 Astra at max effort resolved 58.18% (plus or minus 2.8, 330 trials, $3,267.18 total cost). Xhigh and high scored 57.88% and medium 54.24%.

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