Claude Sonnet 4.6 vs xAI: Grok 4 Fast (free)
Compare Claude Sonnet 4.6 by Anthropic against xAI: Grok 4 Fast (free) by xAI, context windows of 1.0M vs 2.0M, tested across 34 shared challenges. Updated April 2026.
Which is better, Claude Sonnet 4.6 or xAI: Grok 4 Fast (free)?
Claude Sonnet 4.6 and xAI: Grok 4 Fast (free) are both competitive models. Claude Sonnet 4.6 costs $3/M input tokens vs $0/M for xAI: Grok 4 Fast (free). Context windows: 1000K vs 2000K tokens. Compare their real outputs side by side below.
Key Differences Between Claude Sonnet 4.6 and xAI: Grok 4 Fast (free)
Claude Sonnet 4.6 is made by anthropic while xAI: Grok 4 Fast (free) is from xai. Claude Sonnet 4.6 has a 1000K token context window compared to xAI: Grok 4 Fast (free)'s 2000K. On pricing, Claude Sonnet 4.6 costs $3/M input tokens vs $0/M for xAI: Grok 4 Fast (free).
No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.
Style Comparison
Claude Sonnet 4.6 uses 19.1x more emoji
vs
Ask them anything yourself
Some models write identically. You are paying for the brand.
178 models fingerprinted across 32 writing dimensions. Free research.
185x
price gap between models that write identically
178
models
12
clone pairs
32
dimensions
279 AI models invented the same fake scientist.
We read every word. 250 models. 2.14 million words. This is what we found.
