Claude Sonnet 5.5 vs Kimi K3
How Anthropic's Claude Sonnet 5.5 and Moonshot (Kimi)'s Kimi K3 differ on paper, from the specs each provider publishes.
Compare them on your promptBoth answer side by side, free with your own API keys.
Key differences
- Kimi K3 accepts a larger context window: 1.05M tokens versus 1M for Claude Sonnet 5.5.
- Claude Sonnet 5.5 is the newer release (September 2026); Kimi K3 came out in June 2026.
Side by side
| Spec | Claude Sonnet 5.5 | Kimi K3 |
|---|---|---|
| Provider | Anthropic | Moonshot (Kimi) |
| Released | September 2026 | June 2026 |
| Context window | 1M tokens | 1.05M tokens |
| Max output | 128K tokens | 128K tokens |
| Reasoning model | Yes | Yes |
| Price per 1M tokens (in / out) | $2 / $10 | See provider |
| Capabilities | Image input, Reasoning, Coding, Tool calling, Structured output, Extended thinking, Streaming | Image input, Reasoning, Coding, Tool calling, Structured output, Extended thinking, Streaming |
Specs as published by each provider. Benchmarks and output quality aren't covered here; the best test is your own prompts.
Specs only go so far. Ask both.
Send one message and get Claude Sonnet 5.5 and Kimi K3's answers side by side, with response time, tokens and cost for each. You'll need Anthropic and Moonshot (Kimi) keys.
Open Claude Sonnet 5.5 vs Kimi K3