GPT-5.3-Codex vs Grok 4.5
OpenAI GPT-5.3-Codex | SpaceXAI Grok 4.5 | |
|---|---|---|
| Overview | ||
| Company | OpenAI | SpaceXAI |
| Release date | Feb 5 2026 | Jul 8 2026 |
| Access | Proprietary | Proprietary |
| Benchmarks | ||
Nonsense detection BullshitBench v2Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better. | 24% | — |
Agentic coding SWE-Bench ProCan the AI fix real bugs in real software? It's handed actual problems from open-source projects and has to write code that genuinely solves them. Higher is better. | — | 64.7% |
Multilingual coding SWE-Bench MultilingualLike SWE-Bench, but the coding problems span many programming languages, not just one. Tests how broadly the AI can code. Higher is better. | — | 78% |
Agentic coding DeepSWE 1.0Artificial Analysis' independent test of deep, agentic software-engineering work — the AI has to plan and carry out substantial coding tasks end to end. Higher is better. | — | 62% |
Next.js coding Next.js EvalsVercel's open eval of how well AI coding agents build and migrate real Next.js apps — measured as the share of tasks the agent completes successfully. Higher is better. | 83% | — |
Agentic terminal coding Terminal-Bench 2.1Can the AI work in a command-line terminal — running commands and finishing technical setup tasks the way a developer would? Higher is better. | — | 83.3% |
| Timeline | ||
| Release gap | GPT-5.3-Codex shipped 153 days before Grok 4.5 | |
Which is better: GPT-5.3-Codex or Grok 4.5?
GPT-5.3-Codex and Grok 4.5 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. GPT-5.3-Codex shipped 153 days before Grok 4.5, so benchmark comparisons should account for the intervening progress.
Published specifications for these two models are limited — see each model page for the latest details.
Direct benchmark comparisons are unavailable — GPT-5.3-Codex and Grok 4.5 don't publish scores on any of the same benchmarks.
Frequently asked questions
GPT-5.3-Codex was released by OpenAI on Feb 5 2026.
Grok 4.5 was released by SpaceXAI on Jul 8 2026.
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