GPT-5.6 Sol
OpenAI's newest reasoning-tier flagship. Extremely close to Claude on AA Index with strong tool use and broad multimodal coverage.
When to use it
General frontier reasoning, mixed multimodal apps, and OpenAI ecosystem tooling.
Watch-outs
Reasoning modes vary widely in latency and cost; pick effort level carefully.
Benchmarks
Human preference ranking from blind pairwise chats. Higher is better; top frontier models cluster within ~50–80 Elo.
Artificial Analysis composite across agents, coding, science, and general evaluations (v4.1 weighting).
Percent of real GitHub issues resolved end-to-end. Strong signal for agentic coding usefulness.
PhD-level science questions. Separates frontier reasoning models better than saturated knowledge tests.
Harder multi-choice knowledge/reasoning suite than classic MMLU.
Frontier closed-ended academic difficulty across many domains.
More from OpenAI
- GPT-5.5 ProAA 55
Hard reasoning tasks, research assistants, and multimodal product surfaces.
- GPT-5.5AA 51
Default production chat, tools, and mixed workloads on OpenAI.
- GPT-5.4AA 46
Teams already on GPT-5.x infra who need stability over bleeding edge.