OpenAI says GPT-6 models much better at COBOL, Fortran and Visual Basic
OpenAI reports that its GPT‑6 family shows major improvements on low‑resource, legacy programming languages. On MultiLangBench, GPT‑6 Astra reached an average test pass rate of 87.4% across 20 languages (versus ~38% for GPT‑5.6 Terra); GPT‑6 Luna scored 40.3% (≈37.9% for GPT‑5.6 Terra) at much lower cost. On a COBOL migration benchmark, GPT‑6.1 Sol achieved 86.6% accuracy at low reasoning effort (5.4% for GPT‑5.6 Sol) and up to 97.9% with higher reasoning effort.