Model Comparison

GPT-5.6 Luna vs Grok-2 Image 1212Which is better in 2026?

Comparing GPT-5.6 Luna and Grok-2 Image 1212 across benchmarks, pricing, and capabilities.

Verdict: GPT-5.6 Luna vs Grok-2 Image 1212 — which is better?

GPT-5.6 Luna (by OpenAI) and Grok-2 Image 1212 (by xAI) 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.

GPT-5.6 Luna also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose GPT-5.6 Luna if…

  • you process long inputs — it offers a 1,050,000 token context window
  • you want the most recent training data — it shipped Jul 2026

Choose Grok-2 Image 1212 if…

  • you are already invested in the xAI ecosystem

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

GPT-5.6 Luna and Grok-2 Image 1212don'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

GPT-5.6 Luna accepts 1,050,000 input tokens compared to Grok-2 Image 1212's 131,072 tokens. Only GPT-5.6 Luna specifies output context (128,000 tokens).

OpenAI
GPT-5.6 Luna
Input1,050,000 tokens
Output128,000 tokens
xAI
Grok-2 Image 1212
Input131,072 tokens
Output- tokens
Sun Jul 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

GPT-5.6 Luna supports multimodal inputs, whereas Grok-2 Image 1212 does not.

GPT-5.6 Luna can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-5.6 Luna

Text
Images
Audio
Video

Grok-2 Image 1212

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

Grok-2 Image 1212

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5.6 Luna was released on 2026-07-09, while Grok-2 Image 1212 was released on 2024-12-12.

GPT-5.6 Luna is 19 months newer than Grok-2 Image 1212.

GPT-5.6 Luna

Jul 9, 2026

2 weeks ago

1.6yr newer
Grok-2 Image 1212

Dec 12, 2024

1.6 years ago

Knowledge Cutoff

When training data ends

GPT-5.6 Luna has a documented knowledge cutoff of 2026-02-16, while Grok-2 Image 1212'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 Grok-2 Image 1212's cutoff date.

GPT-5.6 Luna

Feb 2026

Grok-2 Image 1212

—

Provider Availability

GPT-5.6 Luna is available from OpenAI. Grok-2 Image 1212 is available from xAI.

GPT-5.6 Luna

openai logo
OpenAI
Input Price:Input: $1.00/1MOutput Price:Output: $6.00/1M

Grok-2 Image 1212

xai logo
xAI
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

OpenAI
Larger context window (1,050,000 tokens)
Supports multimodal inputs
xAI

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 Grok-2 Image 1212 side-by-side, then vote on the output you prefer.

GPT-5.6 Luna
✓ Preferred
Grok-2 Image 1212
Open in Playground
AI Model Comparison Table
Feature
OpenAI
GPT-5.6 Luna
xAI
Grok-2 Image 1212

FAQ

Common questions about GPT-5.6 Luna vs Grok-2 Image 1212.

Which is better, GPT-5.6 Luna or Grok-2 Image 1212?

GPT-5.6 Luna (OpenAI) and Grok-2 Image 1212 (xAI) 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 Grok-2 Image 1212 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%.

What are the context window sizes for GPT-5.6 Luna and Grok-2 Image 1212?

GPT-5.6 Luna supports 1.1M tokens and Grok-2 Image 1212 supports 131K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-5.6 Luna and Grok-2 Image 1212?

Key differences include context window (1.1M vs 131K), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5.6 Luna and Grok-2 Image 1212?

GPT-5.6 Luna is developed by OpenAI and Grok-2 Image 1212 is developed by xAI.

Related comparisons