What is the difference between Claude Opus 4 and Grok Code Fast 1?

Claude Opus 4 is developed by Anthropic while Grok Code Fast 1 is developed by xAI. Claude Opus 4 has a 200K token context window vs Grok Code Fast 1's 256K. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 4 or Grok Code Fast 1?

It depends on your use case. Claude Opus 4 and Grok Code Fast 1 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.

How much does Claude Opus 4 cost compared to Grok Code Fast 1?

Claude Opus 4 costs $15/M input tokens and Grok Code Fast 1 costs $0.2/M input tokens. Grok Code Fast 1 is $14.80/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Claude Opus 4 and Grok Code Fast 1 on Rival?

This page shows a side-by-side comparison of Claude Opus 4 and Grok Code Fast 1 across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

Updated Aug 2025

Claude Opus 4vsGrok Code Fast 1

Grok Code Fast 1 is cheaper than Claude Opus 4 at $0.2/M vs $15/M input tokens.

Claude Opus 4 and Grok Code Fast 1 compared across 53 shared prompts
Spec	Claude Opus 4	Grok Code Fast 1
Input price	$15/M tokens	$0.2/M tokens
Output price	$75/M tokens	$1.5/M tokens
Context window	200K tokens	256K tokens
Weights	Closed	—
Free API (OpenRouter)	No	No
Released	May 2025	Aug 2025
SWE-bench Verified	72.5%	70.8%