head-to-head

OpenAI: GPT-5.6 Luna vs OpenAI: GPT-5.6 Terra (batch)

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

OpenAI: GPT-5.6 Luna OpenAI: GPT-5.6 Terra (batch)
Vendoropenaiopenai
Quality Score100100
Benchmark Score89.493.0
Input Price$0.20/M$1.00/M
Output Price$1.20/M$6.00/M
Context Window1,050,0001,050,000
Max Output128,000128,000
Tool Calling✓✓
Structured Output✓✓
Reasoning Mode✓✓
Vision✓✓
Audio--
Benchmark Scores
ai_index84.590.7
ai_index_agentic75.278.2
ai_index_coding100.0100.0

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-5.6 Terra (batch) costs $2.50, so GPT-5.6 Luna is about 5.0 times cheaper for the same work.

Both read up to 1,050,000 tokens at once, roughly 1,575 pages of text.

On our blended benchmark score GPT-5.6 Terra (batch) leads 93.0 to 89.4.

Across the 20 tasks where they differ, GPT-5.6 Luna scores higher on 7 (Code Completion, Code Documentation, Regex Writing and others), GPT-5.6 Terra (batch) on 13 (SQL Generation, Code Review, Code Refactoring and others).

Pick GPT-5.6 Luna if you need lower cost; pick GPT-5.6 Terra (batch) if you need benchmark performance.

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-5.6 Terra (batch)
SQL Generation 171 172
Code Review 166 168
Code Completion 133 120
Code Refactoring 163 165
Bug Fixing 179 181
Unit Test Generation 154 155
Code Documentation 143 143
Regex Writing 136 136
CI/CD Pipelines 144 145
Frontend Component Design 146 147
Data Analysis 170 171
CSV / Spreadsheet Cleanup 154 154
ETL Scripting 154 155
JSON Extraction 149 139
Bulk Data Labeling 135 125
OCR / Document Parsing 146 147
Table Extraction from PDFs 146 147
Long-Document Summarization 159 160
Short-Form Summarization 132 123
Blog Post Writing 140 140

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

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