Previous-generation coding-optimized model for software engineering.
OpenAI's GPT-5.6 flagship — built for complex reasoning, agentic coding, and long-running professional work.
No shared agent demos for these models yet.
No captured outputs for these models yet.
This model hasn't been benchmarked yet.
Both GPT 5.1 Codex and GPT 5.6 Sol are capable AI models. The best choice depends on your specific use case: consider pricing, context window, speed, and which capabilities (vision, reasoning, audio) you need.
GPT 5.1 Codex has a lower blended cost. GPT 5.1 Codex: $1.25 input / $10.00 output. GPT 5.6 Sol: $5.00 input / $30.00 output.
GPT 5.6 Sol has a larger context window: GPT 5.1 Codex supports 400K tokens vs GPT 5.6 Sol at 1.1M tokens.
Yes, both GPT 5.1 Codex and GPT 5.6 Sol support vision/image input.
Key differences: GPT 5.1 Codex is significantly cheaper. Compare full specs on this page.
If cost is your priority, choose the cheaper option. If you need the highest intelligence for complex tasks, pick the higher-scoring model. For long documents or codebases, choose the larger context window. You can try both GPT 5.1 Codex and GPT 5.6 Sol for free on idapt.app to see which performs better for your specific needs.