head-to-head

OpenAI: GPT-5.6 Luna vs SpaceXAI: Grok 4.3

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

OpenAI: GPT-5.6 Luna SpaceXAI: Grok 4.3
Vendoropenaix-ai
Quality Score100100
Benchmark Score62.339.3
Input Price$0.20/M$1.25/M
Output Price$1.20/M$2.50/M
Context Window1,050,0001,000,000
Max Output128,000900,000
Tool Calling
Structured Output
Reasoning Mode
Vision
Audio--
Benchmark Scores
ai_index61.641.1

Who wins by task?

TaskOpenAI: GPT-5.6 LunaSpaceXAI: Grok 4.3
SQL Generation 141 138
Code Review 143 139
Code Completion 133 120
Code Refactoring 145 142
Bug Fixing 147 143
Unit Test Generation 131 128
Code Documentation 137 134
Regex Writing 125 123
CI/CD Pipelines 127 124
Frontend Component Design 129 126
Data Analysis 133 130
CSV / Spreadsheet Cleanup 136 135
ETL Scripting 136 133
JSON Extraction 131 123
Bulk Data Labeling 129 120
OCR / Document Parsing 134 133
Table Extraction from PDFs 134 133
Long-Document Summarization 147 144
Short-Form Summarization 126 117
Blog Post Writing 129 126

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

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