Model Comparison

GPT-5.6 Luna vs Kimi-k1.5Which is better in 2026?

Comparing GPT-5.6 Luna and Kimi-k1.5 across benchmarks, pricing, and capabilities.

Verdict: GPT-5.6 Luna vs Kimi-k1.5 — which is better?

GPT-5.6 Luna (by OpenAI) and Kimi-k1.5 (by Moonshot AI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Choose GPT-5.6 Luna if…

  • you want the most recent training data — it shipped Jul 2026

Choose Kimi-k1.5 if…

  • you are already invested in the Moonshot AI ecosystem

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

GPT-5.6 Luna and Kimi-k1.5don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only GPT-5.6 Luna specifies input context (1,050,000 tokens). Only GPT-5.6 Luna specifies output context (128,000 tokens).

OpenAI
GPT-5.6 Luna
Input1,050,000 tokens
Output128,000 tokens
Moonshot AI
Kimi-k1.5
Input- tokens
Output- tokens
Sat Jul 18 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both GPT-5.6 Luna and Kimi-k1.5 support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

GPT-5.6 Luna

Text
Images
Audio
Video

Kimi-k1.5

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

GPT-5.6 Luna

Proprietary

Closed source

Kimi-k1.5

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5.6 Luna was released on 2026-07-09, while Kimi-k1.5 was released on 2025-01-20.

GPT-5.6 Luna is 18 months newer than Kimi-k1.5.

GPT-5.6 Luna

Jul 9, 2026

1 weeks ago

1.5yr newer
Kimi-k1.5

Jan 20, 2025

1.5 years ago

Knowledge Cutoff

When training data ends

GPT-5.6 Luna has a documented knowledge cutoff of 2026-02-16, while Kimi-k1.5's cutoff date is not specified.

We can confirm GPT-5.6 Luna's training data extends to 2026-02-16, but cannot make a direct comparison without Kimi-k1.5's cutoff date.

GPT-5.6 Luna

Feb 2026

Kimi-k1.5

—

Outputs Comparison

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Key Takeaways

OpenAI
Larger context window (1,050,000 tokens)
Moonshot AI

No standout differentiators in the data we have for this pair.

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against GPT-5.6 Luna and Kimi-k1.5 side-by-side, then vote on the output you prefer.

GPT-5.6 Luna
✓ Preferred
Kimi-k1.5
Open in Playground
AI Model Comparison Table
Feature
OpenAI
GPT-5.6 Luna
Moonshot AI
Kimi-k1.5

FAQ

Common questions about GPT-5.6 Luna vs Kimi-k1.5.

Which is better, GPT-5.6 Luna or Kimi-k1.5?

GPT-5.6 Luna (OpenAI) and Kimi-k1.5 (Moonshot AI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does GPT-5.6 Luna compare to Kimi-k1.5 in benchmarks?

GPT-5.6 Luna scores Connectors: 99.9%, HealthBench Consensus: 95.1%, GPQA: 92.3%, Search and Function-Calling: 89.7%, Capture-the-Flag Challenges (Internal): 85.2%. Kimi-k1.5 scores MATH-500: 96.2%, CLUEWSC: 91.4%, C-Eval: 88.3%, MMLU: 87.4%, IFEval: 87.2%.

What are the context window sizes for GPT-5.6 Luna and Kimi-k1.5?

GPT-5.6 Luna supports 1.1M tokens and Kimi-k1.5 supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

Who makes GPT-5.6 Luna and Kimi-k1.5?

GPT-5.6 Luna is developed by OpenAI and Kimi-k1.5 is developed by Moonshot AI.

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