AI model comparison
Kimi K3 vs Claude Opus 4.8
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
Moonshot AI
Kimi K3
Kimi K3 is a 2.8T parameter open-weight multimodal reasoning model from Moonshot AI.
- Input / 1M
- $0.90
- Output / 1M
- $14
- Context
- 1.05M
Anthropic
Claude Opus 4.8
Claude Opus 4.8 is Anthropic's most capable generally available model in the Opus family.
- Input / 1M
- $5
- Output / 1M
- $25
- Context
- 1M
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
Kimi K3
2.6x cheaper for a typical chat
Higher intelligence score
Kimi K3
43.6 vs 41.8 on Artificial Analysis
Larger context window
Kimi K3
1.05M vs 1M tokens
Newer release
Kimi K3
Released July 16, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
Claude Opus 4.841.8Coding index
Claude Opus 4.874.3Agentic index
Claude Opus 4.841.9Pricing
Kimi K3 vs Claude Opus 4.8 API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | Claude Opus 4.8 | |
|---|---|---|
| Input tokensPer 1M tokens | $0.90 | $5 |
| Output tokensPer 1M tokens | $14 | $25 |
| Cached input (read)Per 1M tokens | $0.60 | $0.50 |
| Cache writePer 1M tokens | Not available | $6.25 |
| 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 Opus 4.8$22.50Coding task
30K in, 4K out
Claude Opus 4.8$250$115 cachedLong document summary
150K in, 2K out
Claude Opus 4.8$800$125 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | Claude Opus 4.8 | |
|---|---|---|
| Context window | 1.05M tokens | 1M tokens |
| Max output | 944K tokens | 128K tokens |
| Input types | Image, Text, Video | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | Max, High, Low | Max, Extra high, High, Medium, Low |
| Default reasoning effort | Max | High |
| Release date | July 16, 2026 | May 27, 2026 |
Features
Supported features
API features available for each model.
| Metric | Claude Opus 4.8 | |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Supported | Not supported |
| Stop sequences | Supported | Supported |
| Deterministic seed | Supported | Not supported |
| Verbosity control | Not supported | Supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
- Kimi K3 vs Claude Opus 5.5
- Kimi K3 vs Claude Fable 5.1
- Kimi K3 vs GPT-6 Astra
- Kimi K3 vs GPT-6.1 Sol
- Kimi K3 vs Claude Opus 5
- Kimi K3 vs Claude Fable 5
- Kimi K3 vs GLM 5.3
- Kimi K3 vs GPT-6 Sol
- Kimi K3 vs GPT-5.6 Sol
- Kimi K3 vs Gemini 3.8 Flash
- Kimi K3 vs Grok 4.7
- Kimi K3 vs Qwen3.8 Max (0902)
- Kimi K3 vs Grok 4.6
- Kimi K3 vs Claude Haiku 5.5
- Kimi K3 vs GPT-5.6 Terra
- Kimi K3 vs Ling 3.1 Flash
- Kimi K3 vs Claude Opus 4.7
- Kimi K3 vs Qwen3.8 2.4T A95B
- Kimi K3 vs GPT-5.4
- Kimi K3 vs Claude Sonnet 5
- Kimi K3 vs GPT-5.5
Claude Opus 4.8View full model details- Claude Opus 4.8 vs Claude Fable 5.1
- Claude Opus 4.8 vs Claude Opus 5
- Claude Opus 4.8 vs Claude Fable 5
- Claude Opus 4.8 vs GLM 5.3
- Claude Opus 4.8 vs GPT-5.6 Terra
- Claude Opus 4.8 vs Ling 3.1 Flash
- Claude Opus 4.8 vs Gemini 3.8 Flash
- Claude Opus 4.8 vs Claude Opus 4.7
- Claude Opus 4.8 vs DeepSeek V4.1 Flash
- Claude Opus 4.8 vs GPT-5.4
- Claude Opus 4.8 vs GPT-5.5
- Claude Opus 4.8 vs Claude Sonnet 5
- Claude Opus 4.8 vs Claude Opus 4.6
Our take
Kimi K3 is 2.6x cheaper for a typical chat. Kimi K3 scores higher on the Artificial Analysis Intelligence Index (43.6 vs 41.8). Kimi K3 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 or Claude Opus 4.8 cheaper?
Kimi K3 is cheaper for a typical chat (2K input tokens and 500 output tokens). Kimi K3 costs $0.90 per 1M input tokens and $14 per 1M output tokens, while Claude Opus 4.8 costs $5 per 1M input tokens and $25 per 1M output tokens.
Which has a bigger context window, Kimi K3 or Claude Opus 4.8?
Kimi K3 supports up to 1.05M tokens of context, compared with 1M for Claude Opus 4.8.
Is Kimi K3 smarter than Claude Opus 4.8?
On the Artificial Analysis Intelligence Index, Kimi K3 scores 43.6 and Claude Opus 4.8 scores 41.8, putting Kimi K3 ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.
Can I use Kimi K3 and Claude Opus 4.8 at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Kimi K3 and Claude Opus 4.8 answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to Kimi K3 and Claude Opus 4.8 at the same time. Compare the answers side by side and keep the best one.