Model Comparison

Grok 4.5 vs Kimi-k1.5Which is better in 2026?

Comparing Grok 4.5 and Kimi-k1.5 across benchmarks, pricing, and capabilities.

Verdict: Grok 4.5 vs Kimi-k1.5 — which is better?

Grok 4.5 (by xAI) 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 Grok 4.5 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

Grok 4.5 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 Grok 4.5 specifies input context (500,000 tokens).

xAI
Grok 4.5
Input500,000 tokens
Output- 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 Grok 4.5 and Kimi-k1.5 support multimodal inputs.

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

Grok 4.5

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.

Grok 4.5

Proprietary

Closed source

Kimi-k1.5

Proprietary

Closed source

Release Timeline

When each model was launched

Grok 4.5 was released on 2026-07-16, while Kimi-k1.5 was released on 2025-01-20.

Grok 4.5 is 18 months newer than Kimi-k1.5.

Grok 4.5

Jul 16, 2026

2 days ago

1.5yr newer
Kimi-k1.5

Jan 20, 2025

1.5 years ago

Knowledge Cutoff

When training data ends

Grok 4.5 has a documented knowledge cutoff of 2026-02-01, while Kimi-k1.5's cutoff date is not specified.

We can confirm Grok 4.5's training data extends to 2026-02-01, but cannot make a direct comparison without Kimi-k1.5's cutoff date.

Grok 4.5

Feb 2026

Kimi-k1.5

—

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

xAI
Larger context window (500,000 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 Grok 4.5 and Kimi-k1.5 side-by-side, then vote on the output you prefer.

Grok 4.5
✓ Preferred
Kimi-k1.5
Open in Playground
AI Model Comparison Table
Feature
xAI
Grok 4.5
Moonshot AI
Kimi-k1.5

FAQ

Common questions about Grok 4.5 vs Kimi-k1.5.

Which is better, Grok 4.5 or Kimi-k1.5?

Grok 4.5 (xAI) 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 Grok 4.5 compare to Kimi-k1.5 in benchmarks?

Grok 4.5 scores GPQA: 93.0%, Terminal-Bench 2.1: 83.3%, Artificial Analysis Coding Agent Index v1.1: 76.0%, SWE-Bench Pro: 64.7%, AA-Omniscience Index: 63.0%. 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 Grok 4.5 and Kimi-k1.5?

Grok 4.5 supports 500K 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 Grok 4.5 and Kimi-k1.5?

Grok 4.5 is developed by xAI and Kimi-k1.5 is developed by Moonshot AI.

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