Claude Sonnet 4.5 vs Kimi K3
Both have similar output pricing, while Kimi K3 offers a larger context window. Choose Claude Sonnet 4.5 or Kimi K3 based on the trade-off between cost, context, and the benchmarks that matter for your use case.
| Spec | Claude Sonnet 4.5 | Kimi K3 |
|---|---|---|
| Provider | Anthropic | MoonshotAI |
| Input / 1M tokens | $3.00 | $0.45 |
| Output / 1M tokens | $15.00 | $15.00 |
| Context window | 1M | 1M |
| Parameters | — | — |
| Open weights | No | — |
| Released | Sep 2025 | — |
| LiveBench score | 67.9 | — |
| SWE-bench Verified score | 74.8 | — |
| SWE-bench Multilingual score | 67.0 | — |
| LMArena (Chatbot Arena) Elo score | 1438 | 1476 |
| LMArena WebDev Elo score | 1393 | 1655 |
| GPQA Diamond score | 82.3 | 93.1 |
| FrontierMath score | 15.2 | — |
| Epoch Capabilities Index score | 147 | 157 |
FAQ
Is Claude Sonnet 4.5 or Kimi K3 cheaper?
Claude Sonnet 4.5 and Kimi K3 have comparable output pricing.
Which has the larger context window, Claude Sonnet 4.5 or Kimi K3?
Kimi K3 has the larger context window (1M tokens).
Pricing is indicative — confirm with the provider before production use. Highlighted values indicate the better figure for that row.