GPT 5.5 Review: Benchmarks, Pricing, and What Builders Need to Know
OpenAI released GPT 5.5 on 23 April 2026, the first fully retrained base model since GPT-4.5. 1M context, 82.7% Terminal-Bench, 85% ARC-AGI-2. Here is what the benchmarks actually say, where Opus 4.7 still leads, and what it means if you build things.