head-to-head

Sakana: Sakana Namazu vs OpenAI: GPT-5.6 Luna (batch)

Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-09-27.

Sakana: Sakana Namazu OpenAI: GPT-5.6 Luna (batch)
Vendorsakanaopenai
Quality Score100100
Benchmark Score-62.3
Input Price$0.95/M$0.10/M
Output Price$4.00/M$0.60/M
Context Window262,1441,050,000
Max Output65,536128,000
Tool Calling✓✓
Structured Output✓✓
Reasoning Mode✓✓
Vision✓✓
Audio--
Benchmark Scores
ai_index-61.6

The verdict

For a sample job of 1 million input tokens and 250,000 output tokens, GPT-5.6 Luna (batch) costs $0.25 and Sakana Namazu costs $1.95, so GPT-5.6 Luna (batch) is about 7.8 times cheaper for the same work.

GPT-5.6 Luna (batch) reads up to 1,050,000 tokens at once, roughly 1,575 pages of text, against about 393 pages for Sakana Namazu.

Across the 20 tasks where they differ, GPT-5.6 Luna (batch) on 20 (SQL Generation, Code Review, Code Completion and others).

Sakana Namazu was released in August 2026 and GPT-5.6 Luna (batch) in July 2026.

Pick GPT-5.6 Luna (batch) if you need lower cost, long documents or the stronger all-round task scores.

Costs use current list prices per million tokens; page counts assume about 0.75 words per token and 500 words per page.

Who wins by task?

TaskSakana: Sakana NamazuOpenAI: GPT-5.6 Luna (batch)
SQL Generation 130 141
Code Review 126 143
Code Completion 128 133
Code Refactoring 127 145
Bug Fixing 130 147
Unit Test Generation 121 131
Code Documentation 125 137
Regex Writing 119 126
CI/CD Pipelines 117 127
Frontend Component Design 122 129
Data Analysis 124 133
CSV / Spreadsheet Cleanup 128 136
ETL Scripting 122 136
JSON Extraction 131 131
Bulk Data Labeling 128 129
OCR / Document Parsing 128 134
Table Extraction from PDFs 128 134
Long-Document Summarization 129 147
Short-Form Summarization 123 126
Blog Post Writing 118 129

Scores reflect capability match + benchmark data + pricing for each task. Methodology →

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