Previous-generation coding-optimized model for software engineering.
xAI's Opus-class flagship for frontier coding, agentic tool use, and knowledge 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 Grok 4.5 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.
Grok 4.5 has a lower blended cost. GPT 5.1 Codex: $1.25 input / $10.00 output. Grok 4.5: $2.00 input / $6.00 output.
Grok 4.5 has a larger context window: GPT 5.1 Codex supports 400K tokens vs Grok 4.5 at 500K tokens.
Yes, both GPT 5.1 Codex and Grok 4.5 support vision/image input.
GPT 5.1 Codex and Grok 4.5 have similar overall capabilities. The main differences lie in pricing, context window size, and provider-specific strengths. Use this comparison page to review all metrics side by side.
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 Grok 4.5 for free on idapt.app to see which performs better for your specific needs.