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

OpenAI says its models are improving at working with older programming languages, including COBOL, which remains in use across many banks. The company says AI could help modernise these systems as experienced COBOL programmers leave the workforce and migration becomes increasingly pressing.

OpenAI says 40 per cent of the world’s banks still rely on COBOL, and replacing those systems can cost millions to hundreds of millions of dollars. In its MultiLangBench evaluation, GPT-6 Astra passed an average of 87.4 per cent of tests across 20 languages, compared with 26.8 per cent for GPT-5.6 Sol; Astra scored 72 per cent on COBOL. In migration tests, GPT-6.1 Sol achieved up to 97.9 per cent accuracy when preserving programme behaviour, but OpenAI says production use still needs expert review and testing.