Grok 3 Beta vs xAI: Grok 4 Fast (free)
Compare Grok 3 Beta and xAI: Grok 4 Fast (free), both from xAI, context windows of 131K vs 2.0M, tested across 35 shared challenges. Updated May 2026.
Which is better, Grok 3 Beta or xAI: Grok 4 Fast (free)?
Grok 3 Beta and xAI: Grok 4 Fast (free) are both competitive models. Grok 3 Beta costs $2/M input tokens vs $0/M for xAI: Grok 4 Fast (free). Context windows: 131K vs 2000K tokens. Compare their real outputs side by side below.
Key Differences Between Grok 3 Beta and xAI: Grok 4 Fast (free)
Grok 3 Beta is made by xai while xAI: Grok 4 Fast (free) is from xai. Grok 3 Beta has a 131K token context window compared to xAI: Grok 4 Fast (free)'s 2000K. On pricing, Grok 3 Beta costs $2/M input tokens vs $0/M for xAI: Grok 4 Fast (free).
Per 1M tokens
No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.
Style Comparison
xAI: Grok 4 Fast (free) uses 3.0x more headings
