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Claude Mythos 5.1 vs Hermes 3 405B

Claude Mythos 5.1 leads the LLM Stats Score 45.1 to 4.4. Hermes 3 405B is 20.0x cheaper per token.

Anthropic · Nous Research · Updated for 2026

Which is better?

Claude Mythos 5.1 leads the overall LLM Stats Score 45.1 to 4.4, ranking #31 overall.

On price, Hermes 3 405B is roughly 20.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Mythos 5.1 also accepts a larger context window (1,000,000 input tokens), making it the stronger choice for long documents and large codebases.

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 process long inputs — it offers a 1,000,000 token context window
  • you want the most recent training data — it shipped Sep 2026

Choose Hermes 3 405B

  • cost matters — it's about 20.0x cheaper per token
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Core performance indexes
45.1
#31
4.4
#299
44.4
#34
3.8
#297
Cost, coverage & limits
Benchmark wins
Input price
$10.00 / M
$1.00 / M
Output price
$50.00 / M
$1.00 / M
Context window
1,000,000
131,072

Individual benchmarks

1 reported for Claude Mythos 5.1 · 13 for Hermes 3 405B

No common benchmarks found

Claude Mythos 5.1 and Hermes 3 405Bdon'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

Pricing Analysis

Price comparison per million tokens

Hermes 3 405B costs less

For input processing, Claude Mythos 5.1 ($10.00/1M tokens) is 10.0x more expensive than Hermes 3 405B ($1.00/1M tokens).

For output processing, Claude Mythos 5.1 ($50.00/1M tokens) is 50.0x more expensive than Hermes 3 405B ($1.00/1M tokens).

In conclusion, Claude Mythos 5.1 is more expensive than Hermes 3 405B.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Wed Sep 09 2026 • llm-stats.com
Anthropic
Claude Mythos 5.1
Input tokens$10.00
Output tokens$50.00
Best providerAnthropic
Nous Research
Hermes 3 405B
Input tokens$1.00
Output tokens$1.00
Best providerDeepinfra
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

Claude Mythos 5.1 accepts 1,000,000 input tokens compared to Hermes 3 405B's 131,072 tokens. Hermes 3 405B can generate longer responses up to 131,072 tokens, while Claude Mythos 5.1 is limited to 128,000 tokens.

Anthropic
Claude Mythos 5.1
Input1,000,000 tokens
Output128,000 tokens
Nous Research
Hermes 3 405B
Input131,072 tokens
Output131,072 tokens
Wed Sep 09 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Mythos 5.1 supports multimodal inputs, whereas Hermes 3 405B 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

Hermes 3 405B

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Mythos 5.1 is licensed under a proprietary license, while Hermes 3 405B uses Apache 2.0.

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

Claude Mythos 5.1

Proprietary

Closed source

Hermes 3 405B

Apache 2.0

Open weights

Release Timeline

When each model was launched

Claude Mythos 5.1 was released on 2026-09-01, while Hermes 3 405B was released on 2024-10-09.

Claude Mythos 5.1 is 23 months newer than Hermes 3 405B.

Claude Mythos 5.1

Sep 1, 2026

1 weeks ago

1.9yr newer
Hermes 3 405B

Oct 9, 2024

1.9 years ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

Claude Mythos 5.1 is available from Anthropic. Hermes 3 405B is available from DeepInfra.

Claude Mythos 5.1

anthropic logo
Anthropic
Input Price:Input: $10.00/1MOutput Price:Output: $50.00/1M

Hermes 3 405B

deepinfra logo
Deepinfra
Input Price:Input: $1.00/1MOutput Price:Output: $1.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against Claude Mythos 5.1 and Hermes 3 405B side-by-side, then vote on the output you prefer.

Claude Mythos 5.1
✓ Preferred
Hermes 3 405B
Open in Playground

FAQ

Common questions about Claude Mythos 5.1 vs Hermes 3 405B.

Which is better, Claude Mythos 5.1 or Hermes 3 405B?

Claude Mythos 5.1 leads the LLM Stats Score 45.1 to 4.4. Claude Mythos 5.1 is made by Anthropic and Hermes 3 405B is made by Nous Research. 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 Hermes 3 405B in benchmarks?

Claude Mythos 5.1 scores Terminal-Bench 4.0: 60.9%. Hermes 3 405B scores HellaSwag: 90.2%, MT-Bench: 89.3%, BoolQ: 88.9%, Winogrande: 86.3%, ARC-E: 86.2%.

Is Claude Mythos 5.1 cheaper than Hermes 3 405B?

Hermes 3 405B is 10.0x cheaper for input tokens. Claude Mythos 5.1 costs $10.00/M input and $50.00/M output via anthropic. Hermes 3 405B costs $1.00/M input and $1.00/M output via deepinfra.

What are the context window sizes for Claude Mythos 5.1 and Hermes 3 405B?

Claude Mythos 5.1 supports 1.0M tokens and Hermes 3 405B supports 131K 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 Hermes 3 405B?

Key differences include LLM Stats Score (45.1 vs 4.4), context window (1.0M vs 131K), input pricing ($10.00 vs $1.00/M), multimodal support (yes vs no), licensing (Proprietary vs Apache 2.0). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Mythos 5.1 and Hermes 3 405B?

Claude Mythos 5.1 is developed by Anthropic and Hermes 3 405B is developed by Nous Research.