What is the difference between Claude 3 Opus and Grok 4.1 Fast?

Claude 3 Opus is developed by Anthropic while Grok 4.1 Fast is developed by xAI. You can compare their actual outputs across 12 challenges on Rival to see how they differ in practice.

Which is better, Claude 3 Opus or Grok 4.1 Fast?

It depends on your use case. Claude 3 Opus and Grok 4.1 Fast each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 12 challenges so you can judge which fits your needs best.

How can I compare Claude 3 Opus and Grok 4.1 Fast on Rival?

This page shows a side-by-side comparison of Claude 3 Opus and Grok 4.1 Fast 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.

What is the difference between Claude 3 Opus and Grok 4.1 Fast?

Claude 3 Opus is developed by Anthropic while Grok 4.1 Fast is developed by xAI. You can compare their actual outputs across 12 challenges on Rival to see how they differ in practice.

Which is better, Claude 3 Opus or Grok 4.1 Fast?

It depends on your use case. Claude 3 Opus and Grok 4.1 Fast each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 12 challenges so you can judge which fits your needs best.

How can I compare Claude 3 Opus and Grok 4.1 Fast on Rival?

This page shows a side-by-side comparison of Claude 3 Opus and Grok 4.1 Fast 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.

Claude 3 Opus vs Grok 4.1 Fast: Which Is Better?

Updated Nov 2025

Our Verdict

Claude 3 Opus

Grok 4.1 Fast

No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.

Too close to call

API pricing

Cost per 1M tokens

Claude 3 Opus

Input

$15.00

Output

$75.00

Grok 4.1 Fast

Input

—

Output

—

Writing DNA

Style Comparison

Similarity

35%

Grok 4.1 Fast uses 466.5x more bold

Claude 3 Opus

Grok 4.1 Fast

54%Vocabulary67%

14wSentence Length15w

0.48Hedging0.17

0.0Bold4.7

3.0Lists3.7

0.00Emoji0.00

0.00Headings0.99

0.06Transitions0.14

Based on 3 + 24 text responses

Research

What we learned reading every model

Claude 3 Opus and Grok 4.1 Fast have opinions about your brand too.Ask 10 models what they tell people about you. Verbatim receipts.Run the mirror

FAQ

Common questions

Keep exploring

More comparisons

Claude 3 Opus vs MiniMax M3New provider

Claude 3 Opus vs Llama 4 MaverickNew provider

Claude 3 Opus vs GPT-5New provider

Updated Nov 2025

Our Verdict

Claude 3 Opus

Grok 4.1 Fast

No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.

Too close to call

API pricing

Cost per 1M tokens

Claude 3 Opus

Input

$15.00

Output

$75.00

Grok 4.1 Fast

Input

—

Output

—

Writing DNA

Style Comparison

Similarity

35%

Grok 4.1 Fast uses 466.5x more bold

Claude 3 Opus

Grok 4.1 Fast

54%Vocabulary67%

14wSentence Length15w

0.48Hedging0.17

0.0Bold4.7

3.0Lists3.7

0.00Emoji0.00

0.00Headings0.99

0.06Transitions0.14

Based on 3 + 24 text responses

Research

What we learned reading every model

Claude 3 Opus and Grok 4.1 Fast have opinions about your brand too.Ask 10 models what they tell people about you. Verbatim receipts.Run the mirror

FAQ

Common questions

Keep exploring

More comparisons

Claude 3 Opus vs MiniMax M3New provider

Claude 3 Opus vs Llama 4 MaverickNew provider

Claude 3 Opus vs GPT-5New provider