Claude 3.5 Sonnet vs Kimi K2 Base
Claude 3.5 Sonnet and Kimi K2 Base are closely matched at 15.9 and 13.5 on the LLM Stats Score.
Anthropic · Moonshot AI · Updated for 2026
Which is better?
Claude 3.5 Sonnet and Kimi K2 Base are closely matched on the overall LLM Stats Score at 15.9 and 13.5.
In the 5 individual benchmarks reported for both models, Claude 3.5 Sonnet wins 5; this is a narrower head-to-head signal than the composite indexes.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Claude 3.5 Sonnet
- you value its reported benchmark strengths — it wins 5 of 5 exact shared results
Choose Kimi K2 Base
- you want the most recent training data — it shipped Jul 2025
- you need open weights you can self-host or fine-tune
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
9 reported for Claude 3.5 Sonnet · 13 for Kimi K2 Base
Claude 3.5 Sonnet outperforms in 5 benchmarks (GPQA, GSM8k, MATH, MMLU, MMLU-Pro), while Kimi K2 Base is better at 0 benchmarks.
Claude 3.5 Sonnet significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Context Window
Maximum input and output token capacity
Only Claude 3.5 Sonnet specifies input context (200,000 tokens). Only Claude 3.5 Sonnet specifies output context (200,000 tokens).
Input capabilities
Documented input modalities across available providers
Claude 3.5 Sonnet supports multimodal inputs, whereas Kimi K2 Base does not.
Claude 3.5 Sonnet can handle both text and other forms of data like images, making it suitable for multimodal applications.
Claude 3.5 Sonnet
Kimi K2 Base
License
Usage and distribution terms
Claude 3.5 Sonnet 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.
Proprietary
Closed source
MIT
Open weights
Release Timeline
When each model was launched
Claude 3.5 Sonnet was released on 2024-06-21, while Kimi K2 Base was released on 2025-07-11.
Kimi K2 Base is 13 months newer than Claude 3.5 Sonnet.
Jun 21, 2024
2.3 years ago
Jul 11, 2025
1.2 years ago
1.1yr newerKnowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude 3.5 Sonnet and Kimi K2 Base side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude 3.5 Sonnet vs Kimi K2 Base.