GPT-5.5-Pro vs Grok 4.3 Beta
OpenAI GPT-5.5-Pro | SpaceXAI Grok 4.3 Beta | |
|---|---|---|
| Overview | ||
| Company | OpenAI | SpaceXAI |
| Release date | Apr 23 2026 | Apr 17 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. | 36% | 50%Best |
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% | — |
Web browsing BrowseCompCan the AI browse the web and track down hard-to-find answers? Higher is better. | 90.1% | — |
Advanced math FrontierMath · Tier 1–3Very hard, research-level math problems. Tiers 1–3 are the (still extremely difficult) lower tiers. Higher is better. | 52.4% | — |
Advanced math FrontierMath · Tier 4Very hard, research-level math problems. Tier 4 is the hardest — close to what professional research mathematicians tackle. Higher is better. | 39.6% | — |
Knowledge work GDPval (win/tie rate)How often the AI's work matches or beats a human expert's on real knowledge-work tasks. Higher is better. | 82.3% | — |
| Timeline | ||
| Release gap | Grok 4.3 Beta shipped 6 days before GPT-5.5-Pro | |
Which is better: GPT-5.5-Pro or Grok 4.3 Beta?
Grok 4.3 Beta leads GPT-5.5-Pro on 1 of the 1 benchmark they both report (BullshitBench v2). Grok 4.3 Beta shipped 6 days before GPT-5.5-Pro, 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.
On BullshitBench v2, Grok 4.3 Beta leads at 50% vs GPT-5.5-Pro at 36%.
Frequently asked questions
GPT-5.5-Pro was released by OpenAI on Apr 23 2026.
Grok 4.3 Beta was released by SpaceXAI on Apr 17 2026.
Other comparisons
GPT-5.5-Pro vs Claude Sonnet 5Grok 4.3 Beta vs Claude Sonnet 5GPT-5.5-Pro vs Gemini OmniGrok 4.3 Beta vs Gemini OmniGPT-5.5-Pro vs Muse Spark 1.1Grok 4.3 Beta vs Muse Spark 1.1GPT-5.5-Pro vs DeepSeek-V4-ProGrok 4.3 Beta vs DeepSeek-V4-ProGPT-5.5-Pro vs Mistral Medium 3.5Grok 4.3 Beta vs Mistral Medium 3.5GPT-5.5-Pro vs Kimi K2.7 CodeGrok 4.3 Beta vs Kimi K2.7 Code