GPT-5.6 Sol vs Grok 4 Heavy
OpenAI GPT-5.6 Sol | SpaceXAI Grok 4 Heavy | |
|---|---|---|
| Overview | ||
| Company | OpenAI | SpaceXAI |
| Release date | Jun 26 2026 | Jul 9 2025 |
| 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. | 47% | — |
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. | 88% | — |
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. | 88.8% | — |
Community preference Arena Elo (Text)Real people chat with two anonymous AIs side by side and vote for the answer they prefer. Votes become a chess-style Elo rating on arena.ai — it measures which AI people actually like, not test scores. Higher is better. | 1486 | — |
Community preference (code) Arena Elo (Code)Like the text arena, but people vote on which AI writes better code. The votes become a chess-style Elo rating on arena.ai. Higher is better. | 1636 | — |
| Timeline | ||
| Release gap | Grok 4 Heavy shipped 352 days before GPT-5.6 Sol | |
Which is better: GPT-5.6 Sol or Grok 4 Heavy?
GPT-5.6 Sol and Grok 4 Heavy don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Grok 4 Heavy shipped 352 days before GPT-5.6 Sol, 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-5.6 Sol and Grok 4 Heavy don't publish scores on any of the same benchmarks.
Frequently asked questions
GPT-5.6 Sol was released by OpenAI on Jun 26 2026.
Grok 4 Heavy was released by SpaceXAI on Jul 9 2025.
Other comparisons
GPT-5.6 Sol vs Claude Sonnet 5Grok 4 Heavy vs Claude Sonnet 5GPT-5.6 Sol vs Gemini OmniGrok 4 Heavy vs Gemini OmniGPT-5.6 Sol vs Muse Spark 1.1Grok 4 Heavy vs Muse Spark 1.1GPT-5.6 Sol vs DeepSeek-V4-ProGrok 4 Heavy vs DeepSeek-V4-ProGPT-5.6 Sol vs Mistral Medium 3.5Grok 4 Heavy vs Mistral Medium 3.5GPT-5.6 Sol vs Kimi K2.7 CodeGrok 4 Heavy vs Kimi K2.7 Code