KimivsClaude Opus 4
Moonshot AI vs Anthropic — Side-by-side model comparison
Head-to-Head Comparison
| Metric | Kimi | Claude Opus 4 |
|---|---|---|
| Provider | ||
| Arena Rank | — | #1 |
| Context Window | 2M | 200K |
| Input Pricing | Undisclosed/1M tokens | $5.00/1M tokens |
| Output Pricing | Undisclosed/1M tokens | $25.00/1M tokens |
| Parameters | Undisclosed | Undisclosed |
| Open Source | No | No |
| Best For | Ultra-long documents, research, analysis | Complex reasoning, coding, agentic tasks |
| Release Date | Mar 18, 2024 | May 22, 2025 |
Kimi
Kimi is Moonshot AI's flagship model featuring an industry-leading 2 million token context window, the largest publicly available at launch. This extraordinary context length enables processing of entire books, research paper collections, and massive codebases in a single prompt. Developed by a team of former Google and Microsoft researchers in Beijing, Kimi has become one of China's most popular AI assistants, particularly valued for its ability to analyze very long documents.
View Moonshot AI profile →Claude Opus 4
Claude Opus 4 is Anthropic's most powerful AI model, holding the #1 position on the Chatbot Arena leaderboard. It represents a breakthrough in extended thinking and agentic capabilities, able to work autonomously on complex multi-step tasks for hours. With a 200K token context window, it excels at analyzing entire codebases, lengthy legal documents, and research papers in a single pass. The model demonstrates exceptional performance in coding (setting new benchmarks on SWE-bench), advanced reasoning, and nuanced writing tasks. Its agentic capabilities allow it to use tools, navigate computers, and execute multi-step workflows with minimal human oversight. Opus 4 is the preferred choice for enterprises requiring the highest quality output on mission-critical tasks where accuracy and depth matter more than speed or cost.
View Anthropic profile →Key Differences: Kimi vs Claude Opus 4
Kimi supports a larger context window (2M), allowing it to process longer documents in a single request.
When to use Kimi
- +You need to process long documents (2M context)
- +Your use case involves ultra-long documents, research, analysis
When to use Claude Opus 4
- +Your use case involves complex reasoning, coding, agentic tasks
The Verdict
Claude Opus 4 wins our head-to-head comparison with 3 out of 5 category wins. It's the stronger choice for complex reasoning, coding, agentic tasks, though Kimi holds an edge in ultra-long documents, research, analysis.
Last compared: March 2026 · Data sourced from public benchmarks and official pricing pages