OpenAI says its models can help banks migrate from old COBOL programs

OpenAI says its models are now better at building and migrating software in legacy languages like COBOL, Fortran and Visual Basic. On its MultiLangBench suite, GPT-6 Astra averaged an 87.4% pass rate across 20 languages versus 26.8% for GPT-5.6 Sol, while GPT-6.1 Sol reached 97.9% accuracy on behavior-preserving COBOL migrations.

• 40% of the world's banks still rely on COBOL systems
• MultiLangBench: GPT-6 Astra at 87.4% vs 26.8% for GPT-5.6 Sol
• COBOL remains hardest, with Astra at a 72% pass rate
• COBOL migration: GPT-6.1 Sol hits 97.9% accuracy at high reasoning