AI model comparison
Kimi K3.1 Pro vs Claude Sonnet 4.5
Side by side comparison of Kimi K3.1 Pro and Claude Sonnet 4.5 on pricing, benchmark scores, context window, and more.
Kimi K3.1 Pro is Moonshot AI's flagship open-weight multimodal reasoning model and a post-trained successor to Kimi K3, with a 1M-token context window.
- Input / 1M
- $2
- Output / 1M
- $10
- Context
- 1.05M
Claude Sonnet 4.5 is Anthropic’s most advanced Sonnet model to date, optimized for real-world agents and coding workflows.
- Input / 1M
- $3
- Output / 1M
- $15
- Context
- 1M
Comparing image generators? Compare image models
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
Kimi K3.1 Pro
1.5x cheaper for a typical chat
Higher intelligence score
Not available
Not enough benchmark data
Larger context window
Kimi K3.1 Pro
1.05M vs 1M tokens
Newer release
Kimi K3.1 Pro
Released October 23, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
Claude Sonnet 4.5Not availableCoding index
Claude Sonnet 4.552.1Agentic index
Claude Sonnet 4.515.8Pricing
Kimi K3.1 Pro vs Claude Sonnet 4.5 API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | Claude Sonnet 4.5 | |
|---|---|---|
| Input tokensPer 1M tokens | $2 | $3 |
| Output tokensPer 1M tokens | $10 | $15 |
| Cached input (read)Per 1M tokens | $0.20 | $0.30 |
| Cache writePer 1M tokens | Not available | $3.75 |
| Long-context pricingPer 1M tokens, for very long prompts | Same rate at any length | $6 in / $22.50 out above 200K |
| Web searchPer request | Not available | $0.01 |
What it costs in practice
Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.
Chat message
2K in, 500 out
Claude Sonnet 4.5$13.50Coding task
30K in, 4K out
Claude Sonnet 4.5$150$69 cachedLong document summary
150K in, 2K out
Claude Sonnet 4.5$480$75 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | Claude Sonnet 4.5 | |
|---|---|---|
| Context window | 1.05M tokens | 1M tokens |
| Max output | 944K tokens | 64K tokens |
| Input types | Image, Text, Video | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | Max, High, Low, None | Not available |
| Default reasoning effort | Max | Not available |
| Release date | October 23, 2026 | September 29, 2025 |
Features
Supported features
API features available for each model.
| Metric | Claude Sonnet 4.5 | |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Not supported | Supported |
| Stop sequences | Supported | Supported |
| Deterministic seed | Not supported | Not supported |
| Verbosity control | Not supported | Not supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
- Kimi K3.1 Pro vs Claude Opus 5.5
- Kimi K3.1 Pro vs GPT-6 Astra
- Kimi K3.1 Pro vs GPT-6.1 Sol
- Kimi K3.1 Pro vs Claude Sonnet 5.5
- Kimi K3.1 Pro vs GPT-6.1 Terra
- Kimi K3.1 Pro vs Gemini 4 Argon
- Kimi K3.1 Pro vs Claude Fable 5.1
- Kimi K3.1 Pro vs Muse Spark 1.3
- Kimi K3.1 Pro vs Claude Haiku 5.5
- Kimi K3.1 Pro vs Kimi K3
- Kimi K3.1 Pro vs GLM 5.2
- Kimi K3.1 Pro vs Claude Sonnet 5
- Kimi K3.1 Pro vs GPT-6 Sol
- Kimi K3.1 Pro vs Claude Sonnet 4.6
- Kimi K3.1 Pro vs GPT-5.6 Terra
- Kimi K3.1 Pro vs Grok 4.6
- Kimi K3.1 Pro vs Muse Wonder
Claude Sonnet 4.5View full model details- Claude Sonnet 4.5 vs Claude Opus 5.5
- Claude Sonnet 4.5 vs GPT-6.1 Sol
- Claude Sonnet 4.5 vs Claude Sonnet 5.5
- Claude Sonnet 4.5 vs Kimi K3
- Claude Sonnet 4.5 vs Gemini 4 Argon
- Claude Sonnet 4.5 vs Claude Sonnet 5
- Claude Sonnet 4.5 vs Claude Opus 5
- Claude Sonnet 4.5 vs Claude Fable 5.1
- Claude Sonnet 4.5 vs Claude Sonnet 4.6
- Claude Sonnet 4.5 vs Claude Opus 4.8
- Claude Sonnet 4.5 vs Muse Wonder
Our take
Kimi K3.1 Pro is 1.5x cheaper for a typical chat. Kimi K3.1 Pro has the larger context window (1.05M vs 1M tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.
FAQ
Frequently asked questions
Is Kimi K3.1 Pro or Claude Sonnet 4.5 cheaper?
Kimi K3.1 Pro is cheaper for a typical chat (2K input tokens and 500 output tokens). Kimi K3.1 Pro costs $2 per 1M input tokens and $10 per 1M output tokens, while Claude Sonnet 4.5 costs $3 per 1M input tokens and $15 per 1M output tokens.
Which has a bigger context window, Kimi K3.1 Pro or Claude Sonnet 4.5?
Kimi K3.1 Pro supports up to 1.05M tokens of context, compared with 1M for Claude Sonnet 4.5.
Can I use Kimi K3.1 Pro and Claude Sonnet 4.5 at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Kimi K3.1 Pro and Claude Sonnet 4.5 answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to Kimi K3.1 Pro and Claude Sonnet 4.5 at the same time. Compare the answers side by side and keep the best one.