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GPT-6 Luna vs Kimi K2-Instruct-0905

GPT-6 Luna leads the LLM Stats Score 44.5 to 21.6.

OpenAI · Moonshot AI · Updated for 2026

Which is better?

GPT-6 Luna leads the overall LLM Stats Score 44.5 to 21.6, ranking #41 overall.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose GPT-6 Luna

  • overall performance matters — it scores 44.5 and ranks #41 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you want the most recent training data — it shipped Sep 2026

Choose Kimi K2-Instruct-0905

  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

GPT-6 Luna
OpenAI
Kimi K2-Instruct-0905
Moonshot AI
Core performance indexes
LLM Stats Score
44.5
#41
21.6
#192
Reasoning
40.0
#58
21.8
#182
Coding
31.4
#47
9.7
#175
Agents
31.8
#30
-4.2
#186
Cost, coverage & limits
Benchmark wins
—
—
Input price
$0.10 / M
— / M
Output price
$0.50 / M
— / M
Context window
1,050,000
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
GPT-6 Luna
Kimi K2-Instruct-0905
Tool use
22.1#47
6.4#148
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

5 reported for GPT-6 Luna · 29 for Kimi K2-Instruct-0905

No common benchmarks found

GPT-6 Luna and Kimi K2-Instruct-0905don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only GPT-6 Luna specifies input context (1,050,000 tokens). Only GPT-6 Luna specifies output context (128,000 tokens).

OpenAI
GPT-6 Luna
Input1,050,000 tokens
Output128,000 tokens
Moonshot AI
Kimi K2-Instruct-0905
Input- tokens
Output- tokens
Wed Sep 23 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

GPT-6 Luna supports multimodal inputs, whereas Kimi K2-Instruct-0905 does not.

GPT-6 Luna can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-6 Luna

Text
Images
Audio
Video

Kimi K2-Instruct-0905

Text
Images
Audio
Video

License

Usage and distribution terms

GPT-6 Luna is licensed under a proprietary license, while Kimi K2-Instruct-0905 uses MIT.

License differences may affect how you can use these models in commercial or open-source projects.

GPT-6 Luna

Proprietary

Closed source

Kimi K2-Instruct-0905

MIT

Open weights

Release Timeline

When each model was launched

GPT-6 Luna was released on 2026-09-22, while Kimi K2-Instruct-0905 was released on 2025-09-05.

GPT-6 Luna is 13 months newer than Kimi K2-Instruct-0905.

GPT-6 Luna

Sep 22, 2026

0 days ago

1.0yr newer
Kimi K2-Instruct-0905

Sep 5, 2025

1.0 years ago

Knowledge Cutoff

When training data ends

GPT-6 Luna has a documented knowledge cutoff of 2026-05-18, while Kimi K2-Instruct-0905's cutoff date is not specified.

We can confirm GPT-6 Luna's training data extends to 2026-05-18, but cannot make a direct comparison without Kimi K2-Instruct-0905's cutoff date.

GPT-6 Luna

May 2026

Kimi K2-Instruct-0905

—

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against GPT-6 Luna and Kimi K2-Instruct-0905 side-by-side, then vote on the output you prefer.

GPT-6 Luna
✓ Preferred
Kimi K2-Instruct-0905
Open in Playground

FAQ

Common questions about GPT-6 Luna vs Kimi K2-Instruct-0905.

Which is better, GPT-6 Luna or Kimi K2-Instruct-0905?

GPT-6 Luna leads the LLM Stats Score 44.5 to 21.6. GPT-6 Luna is made by OpenAI and Kimi K2-Instruct-0905 is made by Moonshot AI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does GPT-6 Luna compare to Kimi K2-Instruct-0905 in benchmarks?

GPT-6 Luna scores DeepSWE 1.1: 66.6%, OSWorld 2.0: 52.7%, Agents' Last Exam: 50.9%, FrontierCode 1.1: 42.4%, AutomationBench v1.0.6: 20.7%. Kimi K2-Instruct-0905 scores MATH-500: 97.4%, MMLU-Redux: 92.7%, IFEval: 89.8%, AutoLogi: 89.5%, MMLU: 89.5%.

What are the context window sizes for GPT-6 Luna and Kimi K2-Instruct-0905?

GPT-6 Luna supports 1.1M tokens and Kimi K2-Instruct-0905 supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-6 Luna and Kimi K2-Instruct-0905?

Key differences include LLM Stats Score (44.5 vs 21.6), multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-6 Luna and Kimi K2-Instruct-0905?

GPT-6 Luna is developed by OpenAI and Kimi K2-Instruct-0905 is developed by Moonshot AI.

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