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Claude Mythos 5.1 vs Llama 3.1 Nemotron 70B Instruct

Claude Mythos 5.1 leads the LLM Stats Score 45.1 to 0.4.

Anthropic · NVIDIA · Updated for 2026

Which is better?

Claude Mythos 5.1 leads the overall LLM Stats Score 45.1 to 0.4, ranking #31 overall.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude Mythos 5.1

  • overall performance matters — it scores 45.1 and ranks #31 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • you want the most recent training data — it shipped Sep 2026

Choose Llama 3.1 Nemotron 70B Instruct

  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Claude Mythos 5.1
Anthropic
Llama 3.1 Nemotron 70B Instruct
NVIDIA
Core performance indexes
LLM Stats Score
45.1
#31
0.4
#322
Reasoning
44.4
#34
0.1
#315
Cost, coverage & limits
Benchmark wins
—
—
Input price
$10.00 / M
— / M
Output price
$50.00 / M
— / M
Context window
1,000,000
—

Individual benchmarks

1 reported for Claude Mythos 5.1 · 11 for Llama 3.1 Nemotron 70B Instruct

No common benchmarks found

Claude Mythos 5.1 and Llama 3.1 Nemotron 70B Instructdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only Claude Mythos 5.1 specifies input context (1,000,000 tokens). Only Claude Mythos 5.1 specifies output context (128,000 tokens).

Anthropic
Claude Mythos 5.1
Input1,000,000 tokens
Output128,000 tokens
NVIDIA
Llama 3.1 Nemotron 70B Instruct
Input- tokens
Output- tokens
Tue Sep 08 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Mythos 5.1 supports multimodal inputs, whereas Llama 3.1 Nemotron 70B Instruct does not.

Claude Mythos 5.1 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Mythos 5.1

Text
Images
Audio
Video

Llama 3.1 Nemotron 70B Instruct

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Mythos 5.1 is licensed under a proprietary license, while Llama 3.1 Nemotron 70B Instruct uses Llama 3.1 Community License.

License differences may affect how you can use these models in commercial or open-source projects.

Claude Mythos 5.1

Proprietary

Closed source

Llama 3.1 Nemotron 70B Instruct

Llama 3.1 Community License

Open weights

Release Timeline

When each model was launched

Claude Mythos 5.1 was released on 2026-09-01, while Llama 3.1 Nemotron 70B Instruct was released on 2024-10-01.

Claude Mythos 5.1 is 23 months newer than Llama 3.1 Nemotron 70B Instruct.

Claude Mythos 5.1

Sep 1, 2026

1 weeks ago

1.9yr newer
Llama 3.1 Nemotron 70B Instruct

Oct 1, 2024

1.9 years ago

Knowledge Cutoff

When training data ends

Llama 3.1 Nemotron 70B Instruct has a documented knowledge cutoff of 2023-12-01, while Claude Mythos 5.1's cutoff date is not specified.

We can confirm Llama 3.1 Nemotron 70B Instruct's training data extends to 2023-12-01, but cannot make a direct comparison without Claude Mythos 5.1's cutoff date.

Claude Mythos 5.1

—

Llama 3.1 Nemotron 70B Instruct

Dec 2023

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Claude Mythos 5.1 and Llama 3.1 Nemotron 70B Instruct side-by-side, then vote on the output you prefer.

Claude Mythos 5.1
✓ Preferred
Llama 3.1 Nemotron 70B Instruct
Open in Playground

FAQ

Common questions about Claude Mythos 5.1 vs Llama 3.1 Nemotron 70B Instruct.

Which is better, Claude Mythos 5.1 or Llama 3.1 Nemotron 70B Instruct?

Claude Mythos 5.1 leads the LLM Stats Score 45.1 to 0.4. Claude Mythos 5.1 is made by Anthropic and Llama 3.1 Nemotron 70B Instruct is made by NVIDIA. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Mythos 5.1 compare to Llama 3.1 Nemotron 70B Instruct in benchmarks?

Claude Mythos 5.1 scores Terminal-Bench 4.0: 60.9%. Llama 3.1 Nemotron 70B Instruct scores GSM8k: 91.4%, HellaSwag: 85.6%, Winogrande: 84.5%, GSM8K Chat: 81.9%, MMLU Chat: 80.6%.

What are the context window sizes for Claude Mythos 5.1 and Llama 3.1 Nemotron 70B Instruct?

Claude Mythos 5.1 supports 1.0M tokens and Llama 3.1 Nemotron 70B Instruct supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Mythos 5.1 and Llama 3.1 Nemotron 70B Instruct?

Key differences include LLM Stats Score (45.1 vs 0.4), multimodal support (yes vs no), licensing (Proprietary vs Llama 3.1 Community License). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Mythos 5.1 and Llama 3.1 Nemotron 70B Instruct?

Claude Mythos 5.1 is developed by Anthropic and Llama 3.1 Nemotron 70B Instruct is developed by NVIDIA.

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