Model Comparison

Claude Opus 4 vs Kimi K2 Base

Claude Opus 4 significantly outperforms across most benchmarks.

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Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

Claude Opus 4 outperforms in 1 benchmarks (GPQA), while Kimi K2 Base is better at 0 benchmarks.

Claude Opus 4 significantly outperforms across most benchmarks.

Mon Apr 20 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Cost data unavailable.

Lowest available price from all providers
Mon Apr 20 2026 • llm-stats.com
Anthropic
Claude Opus 4
Input tokens$15.00
Output tokens$75.00
Best providerAnthropic
Moonshot AI
Kimi K2 Base
Input tokens$0.00
Output tokens$0.00
Best providerUnknown Organization
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Context Window

Maximum input and output token capacity

Only Claude Opus 4 specifies input context (200,000 tokens). Only Claude Opus 4 specifies output context (32,000 tokens).

Anthropic
Claude Opus 4
Input200,000 tokens
Output32,000 tokens
Moonshot AI
Kimi K2 Base
Input- tokens
Output- tokens
Mon Apr 20 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Claude Opus 4 supports multimodal inputs, whereas Kimi K2 Base does not.

Claude Opus 4 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Opus 4

Text
Images
Audio
Video

Kimi K2 Base

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Opus 4 is licensed under a proprietary license, while Kimi K2 Base uses MIT.

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

Claude Opus 4

Proprietary

Closed source

Kimi K2 Base

MIT

Open weights

Release Timeline

When each model was launched

Claude Opus 4 was released on 2025-05-22, while Kimi K2 Base was released on 2025-07-11.

Kimi K2 Base is 2 months newer than Claude Opus 4.

Claude Opus 4

May 22, 2025

11 months ago

Kimi K2 Base

Jul 11, 2025

9 months ago

1mo newer

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

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Key Takeaways

Anthropic
Larger context window (200,000 tokens)
Supports multimodal inputs
Higher GPQA score (79.6% vs 48.1%)
Moonshot AI
Has open weights
AnthropicClaude Opus 4
Moonshot AIKimi K2 Base
Compare in Playground

Detailed Comparison

AI Model Comparison Table
Feature
Anthropic
Claude Opus 4
Moonshot AI
Kimi K2 Base

FAQ

Common questions about Claude Opus 4 vs Kimi K2 Base

Claude Opus 4 significantly outperforms across most benchmarks. Claude Opus 4 is made by Anthropic and Kimi K2 Base is made by Moonshot AI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.
Claude Opus 4 scores MMMLU: 88.8%, TAU-bench Retail: 81.4%, GPQA: 79.6%, MMMU (validation): 76.5%, AIME 2025: 75.5%. Kimi K2 Base scores C-Eval: 92.5%, GSM8k: 92.1%, MMLU-redux-2.0: 90.2%, MMLU: 87.8%, TriviaQA: 85.1%.
Claude Opus 4 supports 200K tokens and Kimi K2 Base supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.
Key differences include multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.
Claude Opus 4 is developed by Anthropic and Kimi K2 Base is developed by Moonshot AI.