GPT 5.3 Codex vs Grok 4.5
OpenAI's most advanced agentic coding model with 400K context.
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No captured outputs for these models yet.
Frequently Asked Questions: GPT 5.3 Codex vs Grok 4.5▼
Which is better, GPT 5.3 Codex or Grok 4.5?
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Based on the Capability Index, Grok 4.5 scores higher (88.5 vs 87.0). However, "better" depends on your use case — pricing, speed, context window, and specific capability needs all matter.
Which is cheaper, GPT 5.3 Codex or Grok 4.5?
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Grok 4.5 has a lower blended cost. GPT 5.3 Codex: $1.75 input / $14.00 output. Grok 4.5: $2.00 input / $6.00 output.
Which has a larger context window, GPT 5.3 Codex or Grok 4.5?
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Grok 4.5 has a larger context window: GPT 5.3 Codex supports 400K tokens vs Grok 4.5 at 500K tokens.
Do both GPT 5.3 Codex and Grok 4.5 support vision?
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Yes, both GPT 5.3 Codex and Grok 4.5 support vision/image input.
What are the key differences between GPT 5.3 Codex and Grok 4.5?
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GPT 5.3 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.
Which model should I choose for my use case?
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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 5.3 Codex and Grok 4.5 for free on idapt.app to see which performs better for your specific needs.