head-to-head

MoonshotAI: Kimi K3 vs OpenAI: GPT-5.6 Luna Pro (batch)

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

MoonshotAI: Kimi K3 OpenAI: GPT-5.6 Luna Pro (batch)
Vendormoonshotaiopenai
Quality Score100100
Benchmark Score73.9-
Input Price$3.00/M$0.10/M
Output Price$15.00/M$0.60/M
Context Window1,048,5761,050,000
Max Output943,718128,000
Tool Calling✓✓
Structured Output✓✓
Reasoning Mode✓✓
Vision✓✓
Audio--
Benchmark Scores
ai_index71.9-

The verdict

For a sample job of 1 million input tokens and 250,000 output tokens, GPT-5.6 Luna Pro (batch) costs $0.25 and Kimi K3 costs $6.75, so GPT-5.6 Luna Pro (batch) is about 27.0 times cheaper for the same work.

Both take in a similar amount of text: 1,048,576 and 1,050,000 tokens, about 1,573 and 1,575 pages.

Only Kimi K3 offers video input.

Across the 20 tasks where they differ, Kimi K3 scores higher on 16 (SQL Generation, Code Review, Code Refactoring and others), GPT-5.6 Luna Pro (batch) on 4 (Code Completion, JSON Extraction, Bulk Data Labeling and others).

Pick Kimi K3 if you need video input or the stronger all-round task scores; pick GPT-5.6 Luna Pro (batch) if you need lower cost.

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?

TaskMoonshotAI: Kimi K3OpenAI: GPT-5.6 Luna Pro (batch)
SQL Generation 140 133
Code Review 145 132
Code Completion 117 131
Code Refactoring 147 136
Bug Fixing 149 136
Unit Test Generation 132 124
Code Documentation 134 131
Regex Writing 123 119
CI/CD Pipelines 128 120
Frontend Component Design 130 122
Data Analysis 134 124
CSV / Spreadsheet Cleanup 135 133
ETL Scripting 138 128
JSON Extraction 120 131
Bulk Data Labeling 116 129
OCR / Document Parsing 134 131
Table Extraction from PDFs 134 131
Long-Document Summarization 147 137
Short-Form Summarization 116 123
Blog Post Writing 128 121

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

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