What is the difference between Claude Opus 5 and Llama 3.1 405B?

Claude Opus 5 is developed by Anthropic while Llama 3.1 405B is developed by Meta AI. Claude Opus 5 has a 1.0M token context window vs Llama 3.1 405B's 128K. You can compare their actual outputs across 12 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 5 or Llama 3.1 405B?

It depends on your use case. Claude Opus 5 and Llama 3.1 405B 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 much does Claude Opus 5 cost compared to Llama 3.1 405B?

Claude Opus 5 costs $5/M input tokens and Llama 3.1 405B costs $2.7/M input tokens. Llama 3.1 405B is $2.30/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 5 and Llama 3.1 405B on Rival?

This page shows a side-by-side comparison of Claude Opus 5 and Llama 3.1 405B 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 Opus 5 and Llama 3.1 405B?

Claude Opus 5 is developed by Anthropic while Llama 3.1 405B is developed by Meta AI. Claude Opus 5 has a 1.0M token context window vs Llama 3.1 405B's 128K. You can compare their actual outputs across 12 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 5 or Llama 3.1 405B?

It depends on your use case. Claude Opus 5 and Llama 3.1 405B 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 much does Claude Opus 5 cost compared to Llama 3.1 405B?

Claude Opus 5 costs $5/M input tokens and Llama 3.1 405B costs $2.7/M input tokens. Llama 3.1 405B is $2.30/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 5 and Llama 3.1 405B on Rival?

This page shows a side-by-side comparison of Claude Opus 5 and Llama 3.1 405B 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 Opus 5 vs Llama 3.1 405B: Which Is Better?

Updated Jul 2026

Our Verdict

Claude Opus 5

Llama 3.1 405BRunner-up

No community votes yet. On paper, Claude Opus 5 has the edge — newer, bigger context window.

Llama 3.1 405B is 8.1x cheaper per token — worth considering if cost matters.

Too close to call

What do Claude Opus 5 and Llama 3.1 405B say about your brand?

10 models, one question, verbatim receipts.

or peek at a demo: Notion Linear Vercel

API pricing

Cost per 1M tokens

Claude Opus 5

Input

$5.00

Output

$25.00

Llama 3.1 405B

Input

$2.70

1.9× cheaper

Output

$3.10

8.1× cheaper

Llama 3.1 405B is cheaper on both — 1.9× input, 8.1× output

Writing DNA

Style Comparison

Similarity

51%

Claude Opus 5 uses 394.1x more bold

Claude Opus 5

Llama 3.1 405B

54%Vocabulary56%

21wSentence Length15w

0.40Hedging0.41

3.9Bold0.0

1.9Lists1.9

0.02Emoji0.03

0.71Headings0.00

0.05Transitions0.16

Based on 27 + 5 text responses

Research

What we learned reading every model

FAQ

Common questions

Keep exploring

More comparisons

Llama 3.1 405B vs MiniMax M3New provider

Llama 3.1 405B vs Gemini 2.5 Pro Preview 06-05New provider

Llama 3.1 405B vs GPT-5New provider

Updated Jul 2026

Our Verdict

Claude Opus 5

Llama 3.1 405BRunner-up

No community votes yet. On paper, Claude Opus 5 has the edge — newer, bigger context window.

Llama 3.1 405B is 8.1x cheaper per token — worth considering if cost matters.

Too close to call

What do Claude Opus 5 and Llama 3.1 405B say about your brand?

10 models, one question, verbatim receipts.

or peek at a demo: Notion Linear Vercel

API pricing

Cost per 1M tokens

Claude Opus 5

Input

$5.00

Output

$25.00

Llama 3.1 405B

Input

$2.70

1.9× cheaper

Output

$3.10

8.1× cheaper

Llama 3.1 405B is cheaper on both — 1.9× input, 8.1× output

Writing DNA

Style Comparison

Similarity

51%

Claude Opus 5 uses 394.1x more bold

Claude Opus 5

Llama 3.1 405B

54%Vocabulary56%

21wSentence Length15w

0.40Hedging0.41

3.9Bold0.0

1.9Lists1.9

0.02Emoji0.03

0.71Headings0.00

0.05Transitions0.16

Based on 27 + 5 text responses

Research

What we learned reading every model

FAQ

Common questions

Keep exploring

More comparisons

Llama 3.1 405B vs MiniMax M3New provider

Llama 3.1 405B vs Gemini 2.5 Pro Preview 06-05New provider

Llama 3.1 405B vs GPT-5New provider