Claude Fable 5 vs Grok 4.5
Anthropic Claude Fable 5 | SpaceXAI Grok 4.5 | |
|---|---|---|
| Overview | ||
| Company | Anthropic | SpaceXAI |
| Release date | Jun 9 2026 | Jul 8 2026 |
| Access | Proprietary | Proprietary |
| Specifications | ||
Context window | 1M | — |
| 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. | 56% | — |
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. | 80.3%Best | 64.7% |
Coding SWE-Bench VerifiedReal coding tasks pulled from open-source projects — the AI has to find and fix actual bugs. A human-checked version of the original SWE-Bench. Higher is better. | 95.5% | — |
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 CursorBench v3.1Cursor's own test of harder, real-world coding tasks inside a code editor. Higher is better. | 72.9% | — |
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. | 66.1%Best | 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. | 92% | — |
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%Best | 83.3% |
Agentic computer use OSWorld-VerifiedCan the AI actually operate a computer — clicking, typing, and using real apps — to finish tasks on its own? Higher is better. | 85% | — |
Knowledge work GDPval-AAMeasures how well the AI does economically valuable knowledge work, judged against human experts. Shown as a rating (like a chess Elo) — higher is better. | 1932 | — |
| Timeline | ||
| Release gap | Claude Fable 5 shipped 29 days before Grok 4.5 | |
Which is better: Claude Fable 5 or Grok 4.5?
Claude Fable 5 leads Grok 4.5 on 3 of the 3 benchmarks they both report (SWE-Bench Pro, DeepSWE 1.0, Terminal-Bench 2.1). Claude Fable 5 shipped 29 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.
On SWE-Bench Pro, Claude Fable 5 leads at 80.3% vs Grok 4.5 at 64.7%. On DeepSWE 1.0, Claude Fable 5 leads at 66.1% vs Grok 4.5 at 62%. On Terminal-Bench 2.1, Claude Fable 5 leads at 88% vs Grok 4.5 at 83.3%.
Frequently asked questions
Claude Fable 5 was released by Anthropic on Jun 9 2026.
Grok 4.5 was released by SpaceXAI on Jul 8 2026.
Claude Fable 5 leads on SWE-Bench Pro — Claude Fable 5 80.3% vs Grok 4.5 64.7%.
Other comparisons
Claude Fable 5 vs GPT-5.6 SolGrok 4.5 vs GPT-5.6 SolClaude Fable 5 vs Gemini OmniGrok 4.5 vs Gemini OmniClaude Fable 5 vs Muse SparkGrok 4.5 vs Muse SparkClaude Fable 5 vs DeepSeek-V4-ProGrok 4.5 vs DeepSeek-V4-ProClaude Fable 5 vs Mistral Medium 3.5Grok 4.5 vs Mistral Medium 3.5Claude Fable 5 vs Kimi K2.7 CodeGrok 4.5 vs Kimi K2.7 Code