Kimi K2 API — Model Reference and Integration Guide
Quick Answer
Kimi K2 API is Moonshot AI's cost-effective language model at $0.14 per million input tokens — 10x cheaper than K2.5. It supports 128K context, the kimi k2 instruct api variant for structured tasks, and full OpenAI SDK compatibility. Best for high-volume chatbots and content generation applications.
What is Kimi K2 API
The kimi k2 api is the economical model in Moonshot AI's lineup, designed for developers who need reliable language model capabilities at the lowest possible cost. While it doesn't match K2.5's reasoning depth, kimi k2 api delivers strong performance for general-purpose tasks at a fraction of the price.
The model comes in two variants: the standard kimi-k2 for general conversation and the
kimi k2 instruct api (kimi-k2-instruct) for tasks requiring precise instruction following.
Kimi K2 Specifications
| Specification | Kimi K2 | Kimi K2 Instruct |
|---|---|---|
| Model ID | kimi-k2 | kimi-k2-instruct |
| Context Window | 128K tokens | 128K tokens |
| Input Price | $0.14 / 1M tokens | $0.14 / 1M tokens |
| Output Price | $0.42 / 1M tokens | $0.42 / 1M tokens |
| Vision | No | No |
| Thinking Mode | Yes | No |
| Function Calling | Yes | Yes |
| Free Tier | Available | Available |
Kimi K2 vs K2.5 Feature Comparison
| Feature | Kimi K2 | Kimi K2.5 |
|---|---|---|
| Input Price | $0.14 | $1.40 |
| Output Price | $0.42 | $4.20 |
| Context Window | 128K | 128K |
| Vision Support | No | Yes |
| Code Quality | Good | Excellent |
| Reasoning Depth | Basic | Advanced |
| Best For | High-volume, cost-sensitive | Quality-critical production |
Kimi K2 API Pricing
Kimi k2 api pricing is the most affordable option in the Kimi family. At $0.14 per million input tokens, it costs 96% less than GPT-4o and 90% less than Claude Sonnet 4. This makes the kimi k2 api ideal for startups, prototypes, and high-volume production workloads where cost is the primary concern. For complete pricing details, see our Kimi API Pricing page.
Frequently Asked Questions About Kimi API
What is Kimi K2 API best for?
Kimi K2 API is optimized for cost-sensitive, high-volume applications such as chatbots, content summarization, simple Q&A, and batch processing. At $0.14 per million input tokens, it's 10x cheaper than K2.5 while maintaining solid general performance.
What is the difference between K2 and K2 Instruct?
Kimi K2 Instruct (kimi-k2-instruct) is fine-tuned to follow structured instructions more precisely. Use K2 for general conversation and K2 Instruct for tasks requiring specific output formats, JSON responses, or structured data extraction.
Can I use Kimi K2 API for coding?
Yes, but K2.5 is recommended for complex coding tasks. Kimi K2 handles simpler coding tasks like code completion, basic debugging, and boilerplate generation effectively. For complex multi-file refactoring, use K2.5 for better results.
Is Kimi K2 API free?
Kimi K2 API offers free tier access through Moonshot's platform with limited monthly tokens. The K2 model is the most affordable option in the Kimi family at $0.14 per million input tokens, making it accessible for individual developers and small projects.
What is Kimi K2 API context window?
Kimi K2 API supports the same 131,072 token (128K) context window as K2.5. This allows processing of long documents and extended conversations at a fraction of the cost of the flagship model.
Summary
The kimi k2 api delivers solid general-purpose LLM capabilities at an unmatched price point. For cost-sensitive applications, it's the best value in the kimi api ecosystem. Pair it with K2.5 for complex tasks in a hybrid deployment strategy.