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Claude Sonnet 5.5 vs Sakana Namazu

Claude Sonnet 5.5 leads the LLM Stats Score 58.4 to 41.7. Sakana Namazu is 2.3x cheaper per token.

Anthropic · Sakana AI · Updated for 2026

Which is better?

Claude Sonnet 5.5 leads the overall LLM Stats Score 58.4 to 41.7, ranking #2 overall.

On price, Sakana Namazu is roughly 2.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Sonnet 5.5 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 Sonnet 5.5

  • overall performance matters — it scores 58.4 and ranks #2 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 Sakana Namazu

  • cost matters — it's about 2.3x cheaper per token

At a glance

The differences that matter most.

Claude Sonnet 5.5
Anthropic
Sakana Namazu
Sakana AI
Core performance indexes
LLM Stats Score
58.4
#2
41.7
#67
Reasoning
57.2
#3
41.5
#61
Cost, coverage & limits
Benchmark wins
—
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Input price
$2.00 / M
$0.95 / M
Output price
$10.00 / M
$4.00 / M
Context window
1,000,000
256,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Claude Sonnet 5.5
Sakana Namazu
Math
38.7#25
37.9#28
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

47 reported for Claude Sonnet 5.5 · 3 for Sakana Namazu

No common benchmarks found

Claude Sonnet 5.5 and Sakana Namazudon'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

Sakana Namazu costs less

For input processing, Claude Sonnet 5.5 ($2.00/1M tokens) is 2.1x more expensive than Sakana Namazu ($0.95/1M tokens).

For output processing, Claude Sonnet 5.5 ($10.00/1M tokens) is 2.5x more expensive than Sakana Namazu ($4.00/1M tokens).

In conclusion, Claude Sonnet 5.5 is more expensive than Sakana Namazu.*

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

Lowest available price from all providers
Thu Oct 22 2026 • llm-stats.com
Anthropic
Claude Sonnet 5.5
Input tokens$2.00
Output tokens$10.00
Best providerAnthropic
Sakana AI
Sakana Namazu
Input tokens$0.95
Output tokens$4.00
Best providerUnknown Organization
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

Claude Sonnet 5.5 accepts 1,000,000 input tokens compared to Sakana Namazu's 256,000 tokens. Sakana Namazu can generate longer responses up to 256,000 tokens, while Claude Sonnet 5.5 is limited to 128,000 tokens.

Anthropic
Claude Sonnet 5.5
Input1,000,000 tokens
Output128,000 tokens
Sakana AI
Sakana Namazu
Input256,000 tokens
Output256,000 tokens
Thu Oct 22 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Sonnet 5.5 and Sakana Namazu support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Claude Sonnet 5.5

Text
Images
Audio
Video

Sakana Namazu

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Sonnet 5.5

Proprietary

Closed source

Sakana Namazu

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Sonnet 5.5 was released on 2026-09-28, while Sakana Namazu was released on 2026-08-03.

Claude Sonnet 5.5 is 2 months newer than Sakana Namazu.

Claude Sonnet 5.5

Sep 28, 2026

3 weeks ago

1mo newer
Sakana Namazu

Aug 3, 2026

2 months ago

Knowledge Cutoff

When training data ends

Claude Sonnet 5.5 has a documented knowledge cutoff of 2026-06-01, while Sakana Namazu's cutoff date is not specified.

We can confirm Claude Sonnet 5.5's training data extends to 2026-06-01, but cannot make a direct comparison without Sakana Namazu's cutoff date.

Claude Sonnet 5.5

Jun 2026

Sakana Namazu

—

Provider Availability

Claude Sonnet 5.5 is available from Anthropic. Sakana Namazu is available from Sakana AI.

Claude Sonnet 5.5

anthropic logo
Anthropic
Input Price:Input: $2.00/1MOutput Price:Output: $10.00/1M

Sakana Namazu

sakana logo
Unknown Organization
Input Price:Input: $0.95/1MOutput Price:Output: $4.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Sonnet 5.5 and Sakana Namazu side-by-side, then vote on the output you prefer.

Claude Sonnet 5.5
✓ Preferred
Sakana Namazu
Open in Playground

FAQ

Common questions about Claude Sonnet 5.5 vs Sakana Namazu.

Which is better, Claude Sonnet 5.5 or Sakana Namazu?

Claude Sonnet 5.5 leads the LLM Stats Score 58.4 to 41.7. Claude Sonnet 5.5 is made by Anthropic and Sakana Namazu is made by Sakana AI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Sonnet 5.5 compare to Sakana Namazu in benchmarks?

Claude Sonnet 5.5 scores BenchCAD (with Python tool): 96.3%, ArXivMath (with tools): 95.2%, Global-MMLU: 92.1%, MILU: 91.6%, SWE-bench Multilingual: 90.3%. Sakana Namazu scores AIME 2026: 96.7%, LiveCodeBench v6: 90.3%, MMLU-Pro: 90.3%.

Is Claude Sonnet 5.5 cheaper than Sakana Namazu?

Sakana Namazu is 2.1x cheaper for input tokens. Claude Sonnet 5.5 costs $2.00/M input and $10.00/M output via anthropic. Sakana Namazu costs $0.95/M input and $4.00/M output via sakana.

What are the context window sizes for Claude Sonnet 5.5 and Sakana Namazu?

Claude Sonnet 5.5 supports 1.0M tokens and Sakana Namazu supports 256K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Sonnet 5.5 and Sakana Namazu?

Key differences include LLM Stats Score (58.4 vs 41.7), context window (1.0M vs 256K), input pricing ($2.00 vs $0.95/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Sonnet 5.5 and Sakana Namazu?

Claude Sonnet 5.5 is developed by Anthropic and Sakana Namazu is developed by Sakana AI.

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