Model Comparison

Kimi-k1.5 vs Llama 3.1 405B InstructWhich is better in 2026?

Both models are evenly matched across the benchmarks.

Verdict: Kimi-k1.5 vs Llama 3.1 405B Instruct — which is better?

Kimi-k1.5 (by Moonshot AI) and Llama 3.1 405B Instruct (by Meta) 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.

Kimi-k1.5 outperforms in 1 benchmarks (MMLU), while Llama 3.1 405B Instruct is better at 1 benchmark (IFEval). Both models are evenly matched across the benchmarks.

Choose Kimi-k1.5 if…

  • you want the most recent training data — it shipped Jan 2025

Choose Llama 3.1 405B Instruct if…

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

Performance Benchmarks

Comparative analysis across standard metrics

2 benchmarks

Kimi-k1.5 outperforms in 1 benchmarks (MMLU), while Llama 3.1 405B Instruct is better at 1 benchmark (IFEval).

Both models are evenly matched across the benchmarks.

Mon Aug 03 2026 • llm-stats.com

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only Llama 3.1 405B Instruct specifies input context (128,000 tokens). Only Llama 3.1 405B Instruct specifies output context (128,000 tokens).

Moonshot AI
Kimi-k1.5
Input- tokens
Output- tokens
Meta
Llama 3.1 405B Instruct
Input128,000 tokens
Output128,000 tokens
Mon Aug 03 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Kimi-k1.5 supports multimodal inputs, whereas Llama 3.1 405B Instruct does not.

Kimi-k1.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Kimi-k1.5

Text
Images
Audio
Video

Llama 3.1 405B Instruct

Text
Images
Audio
Video

License

Usage and distribution terms

Kimi-k1.5 is licensed under a proprietary license, while Llama 3.1 405B Instruct uses Llama 3.1 Community License.

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

Kimi-k1.5

Proprietary

Closed source

Llama 3.1 405B Instruct

Llama 3.1 Community License

Open weights

Release Timeline

When each model was launched

Kimi-k1.5 was released on 2025-01-20, while Llama 3.1 405B Instruct was released on 2024-07-23.

Kimi-k1.5 is 6 months newer than Llama 3.1 405B Instruct.

Kimi-k1.5

Jan 20, 2025

1.5 years ago

6mo newer
Llama 3.1 405B Instruct

Jul 23, 2024

2.0 years ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Moonshot AI
Supports multimodal inputs
Higher MMLU score (87.4% vs 87.3%)
Meta
Larger context window (128,000 tokens)
Has open weights
Higher IFEval score (88.6% vs 87.2%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Kimi-k1.5 and Llama 3.1 405B Instruct side-by-side, then vote on the output you prefer.

Kimi-k1.5
✓ Preferred
Llama 3.1 405B Instruct
Open in Playground
AI Model Comparison Table
Feature
Moonshot AI
Kimi-k1.5
Meta
Llama 3.1 405B Instruct

FAQ

Common questions about Kimi-k1.5 vs Llama 3.1 405B Instruct.

Which is better, Kimi-k1.5 or Llama 3.1 405B Instruct?

Both models are evenly matched across the benchmarks. Kimi-k1.5 is made by Moonshot AI and Llama 3.1 405B Instruct is made by Meta. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Kimi-k1.5 compare to Llama 3.1 405B Instruct in benchmarks?

Kimi-k1.5 scores MATH-500: 96.2%, CLUEWSC: 91.4%, C-Eval: 88.3%, MMLU: 87.4%, IFEval: 87.2%. Llama 3.1 405B Instruct scores ARC-C: 96.9%, GSM8k: 96.8%, API-Bank: 92.0%, Multilingual MGSM (CoT): 91.6%, HumanEval: 89.0%.

What are the context window sizes for Kimi-k1.5 and Llama 3.1 405B Instruct?

Kimi-k1.5 supports an unknown number of tokens and Llama 3.1 405B Instruct supports 128K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Kimi-k1.5 and Llama 3.1 405B Instruct?

Key differences include multimodal support (yes vs no), licensing (Proprietary vs Llama 3.1 Community License). See the full comparison above for benchmark-by-benchmark results.

Who makes Kimi-k1.5 and Llama 3.1 405B Instruct?

Kimi-k1.5 is developed by Moonshot AI and Llama 3.1 405B Instruct is developed by Meta.

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