GPT-5.3-Codex vs Grok 4.5
GPT-5.3-Codex leads in 2 of 8 categories
Arena ELO
Tie
Cheaper
GPT-5.3-Codex
Faster
Tie
Detailed Comparison
| Category | GPT-5.3-Codex | Grok 4.5 |
|---|---|---|
| Provider | OpenAI | xAI |
| Context Window | 128K | 128K |
| Input Price ($/1M) | $1.75 WIN | N/A |
| Output Price ($/1M) | $14 WIN | N/A |
| Arena ELO | N/A | N/A |
| Coding | N/A | N/A |
| Reasoning | N/A | N/A |
| Speed (tokens/sec) | N/A | N/A |
| Open Source | No | No |
Frequently Asked Questions
Which has a larger context window?
GPT-5.3-Codex supports 128K context, while Grok 4.5 supports 128K.
Is GPT-5.3-Codex or Grok 4.5 open source?
GPT-5.3-Codex is proprietary. Grok 4.5 is proprietary.
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