head-to-head

OpenAI: GPT-5.6 Luna vs OpenAI: GPT-5.4 Mini

Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-11-07.

OpenAI: GPT-5.6 Luna OpenAI: GPT-5.4 Mini
Vendoropenaiopenai
Quality Score100100
Benchmark Score89.470.8
Input Price$0.20/M$0.75/M
Output Price$1.20/M$4.50/M
Context Window1,050,000400,000
Max Output128,000128,000
Tool Calling✓✓
Structured Output✓✓
Reasoning Mode✓✓
Vision✓✓
Audio--
Benchmark Scores
ai_index84.566.0
ai_index_agentic75.249.8
ai_index_coding100.092.5

The verdict

For a sample job of 1 million input tokens and 250,000 output tokens, GPT-5.6 Luna costs $0.50 and GPT-5.4 Mini costs $1.88, so GPT-5.6 Luna is about 3.8 times cheaper for the same work.

GPT-5.6 Luna reads up to 1,050,000 tokens at once, roughly 1,575 pages of text, against about 600 pages for GPT-5.4 Mini.

On our blended benchmark score GPT-5.6 Luna leads 89.4 to 70.8.

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

GPT-5.6 Luna was released in July 2026 and GPT-5.4 Mini in March 2026.

Pick GPT-5.6 Luna if you need lower cost, long documents, benchmark performance 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?

TaskOpenAI: GPT-5.6 LunaOpenAI: GPT-5.4 Mini
SQL Generation 171 164
Code Review 166 159
Code Completion 133 132
Code Refactoring 163 158
Bug Fixing 179 170
Unit Test Generation 154 148
Code Documentation 143 140
Regex Writing 136 132
CI/CD Pipelines 144 139
Frontend Component Design 146 141
Data Analysis 170 160
CSV / Spreadsheet Cleanup 154 151
ETL Scripting 154 149
JSON Extraction 149 146
Bulk Data Labeling 135 133
OCR / Document Parsing 146 144
Table Extraction from PDFs 146 144
Long-Document Summarization 159 154
Short-Form Summarization 132 129
Blog Post Writing 140 136

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

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