head-to-head

OpenAI: GPT-5.6 Luna vs Google: Gemma 4 31B

Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-09-23.

OpenAI: GPT-5.6 Luna Google: Gemma 4 31B
Vendoropenaigoogle
Quality Score100100
Benchmark Score62.353.7
Input Price$0.20/M$0.09/M
Output Price$1.20/M$0.34/M
Context Window1,050,000262,144
Max Output128,00016,384
Tool Calling
Structured Output
Reasoning Mode
Vision
Audio--
Benchmark Scores
ai_index61.631.3
eqbench-70.8

Who wins by task?

TaskOpenAI: GPT-5.6 LunaGoogle: Gemma 4 31B
SQL Generation 141 139
Code Review 143 140
Code Completion 133 131
Code Refactoring 145 141
Bug Fixing 147 144
Unit Test Generation 131 130
Code Documentation 137 134
CI/CD Pipelines 127 126
Frontend Component Design 129 128
Data Analysis 133 132
CSV / Spreadsheet Cleanup 136 133
ETL Scripting 136 133
JSON Extraction 131 131
Bulk Data Labeling 129 129
OCR / Document Parsing 134 131
Table Extraction from PDFs 134 131
Long-Document Summarization 147 143
Short-Form Summarization 126 126
Blog Post Writing 129 127

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

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