Kimi K2 vs GPT-4o: Which Best for AI Agent?

Choosing the right model for your AI agent is crucial. Kimi K2 and GPT-4o are both top choices, but they have different strengths. This guide compares them to help you pick the best fit for your AI agent project.

Kimi K2 vs GPT-4o: Basic Introduction

Category	Kimi K2	GPT-4o
Basic Info	32 billion activated parameters, 1 trillion total parameters	Multimodal flagship model from OpenAI; parameter count not publicly disclosed (likely tens to hundreds of billions)
Open	✅ Open-source	❌ Closed-source
Mixture of Experts (MoE)	MoE architecture	Likely uses MoE
Variants	Foundation model for researchers and builders. Best for fine-tuning and custom solutions. Post-trained model for general-purpose chat and agent tasks. Reflex-grade for fast responses without extended thinking.	–
Capabilities	Text-to-text	Multimodal (text, image, audio, video)
Input context length	128,000 tokens	128,000 tokens
Output context length	16,000 tokens	16,384 tokens
Language Strength	Strong in both Chinese and English	Strong multilingual abilities; exceptional in English
Hardware	Requires 1.09 TB disk space for full model	Deployment details not disclosed;

Kimi K2 vs GPT-4o: Performance

• Kimi K2 generally outperforms GPT-4o in reasoning, math, multilingual QA, coding, and tool use.
• GPT‑4o still holds some edge in simple QA (SimpleQA) and one tool benchmark (AceBench).

Kimi K2 vs GPT-4o: Speed

GPT-4o is consistently faster than Kimi K2 in both output speed and response latency, across all tested input sizes. The difference is especially large in output speed per second. For very long input contexts (100k tokens), the time to first token gap narrows, but GPT-4o still leads.

Kimi K2 vs GPT-4o: Price

Kimi K2’s Price vs GPT-4o’s Price

GPT-4o is approximately four times more expensive than Kimi K2 Instruct. And Novita AI is the best provider of Kimi K2 !

Kimi K2’s Price vs Other Models’ Prices

The price is the lowest among all compatible models, like gemini 2.5 flash, Llama scout,gpt-4.1 and so on.

Kimi K2 vs GPT-4o: Best Pick for AI Agent

If you need open-source, strong capabilities, and low cost, choose Kimi K2.

If you value speed, multimodality, and easy integration, and cost is less of a concern, choose GPT-4o.

How to Access Kimi K2 via API?

Step 1: Log In and Access the Model Library

Log in to your account and click on the Model Library button.

Step 2: Choose Your Model

Browse through the available options and select the model that suits your needs.

Step 3: Start Your Free Trial

Begin your free trial to explore the capabilities of the selected model.

Step 4: Get Your API Key

To authenticate with the API, we will provide you with a new API key. Entering the “Settings“ page, you can copy the API key as indicated in the image.

Step 5: Install the API

Install API using the package manager specific to your programming language.

After installation, import the necessary libraries into your development environment. Initialize the API with your API key to start interacting with Novita AI LLM. This is an example of using chat completions API for python users.

from openai import OpenAI
  
client = OpenAI(
    base_url="https://api.novita.ai/v3/openai",
    api_key="session_1g0vYAKH0Oir6vI6y4PZIGyFLVvuJiJDx0jZiEeYivQFmDr15mi83mWi-_bdrs0C-Q2hk281SCn1f4oUB49loQ==",
)

model = "moonshotai/kimi-k2-instruct"
stream = True # or False
max_tokens = 65536
system_content = ""Be a helpful assistant""
temperature = 1
top_p = 1
min_p = 0
top_k = 50
presence_penalty = 0
frequency_penalty = 0
repetition_penalty = 1
response_format = { "type": "text" }

chat_completion_res = client.chat.completions.create(
    model=model,
    messages=[
        {
            "role": "system",
            "content": system_content,
        },
        {
            "role": "user",
            "content": "Hi there!",
        }
    ],
    stream=stream,
    max_tokens=max_tokens,
    temperature=temperature,
    top_p=top_p,
    presence_penalty=presence_penalty,
    frequency_penalty=frequency_penalty,
    response_format=response_format,
    extra_body={
      "top_k": top_k,
      "repetition_penalty": repetition_penalty,
      "min_p": min_p
    }
  )

if stream:
    for chunk in chat_completion_res:
        print(chunk.choices[0].delta.content or "", end="")
else:
    print(chat_completion_res.choices[0].message.content)
  
  

How to Access Kimi K2 in Claude Code?

1.Getting Your API Key on Novita AI

Sign up for a Novita AI account to get started with free trial credits. Navigate to the Key Management page in your dashboard and click “Create New Key.”

Copy the generated API key immediately and store it securely – it won’t be displayed again. You’ll need this key for the configuration steps below.

2.Installing Claude Code

Before installing Claude Code, ensure your system meets the minimum requirements. Node.js 18 or higher must be installed on your local environment. You can verify your Node.js version by running node --version in your terminal.

For Windows

Open Command Prompt and execute the following commands:

npm install -g @anthropic-ai/claude-code
npx win-claude-code@latest

The global installation ensures Claude Code is accessible from any directory on your system. The npx win-claude-code@latest command downloads and runs the latest Windows-specific version.

For Mac and Linux

Open Terminal and run:

npm install -g @anthropic-ai/claude-code

Mac users can proceed directly with the global installation without requiring additional platform-specific commands. The installation process automatically configures the necessary dependencies and PATH variables.

3.Setting Up Environment Variables

Environment variables configure Claude Code to use Kimi-K2 through Novita AI’s API endpoints. These variables tell Claude Code where to send requests and how to authenticate.

For Windows

Open Command Prompt and set the following environment variables:

set ANTHROPIC_BASE_URL=https://api.novita.ai/anthropic
set ANTHROPIC_AUTH_TOKEN=<Novita API Key>
set ANTHROPIC_MODEL=moonshotai/kimi-k2-instruct
set ANTHROPIC_SMALL_FAST_MODEL=moonshotai/kimi-k2-instruct

Replace <Novita API Key> with your actual API key obtained from the Novita AI platform. These variables remain active for the current session and must be reset if you close the Command Prompt.

For Mac and Linux

Open Terminal and export the following environment variables:

export ANTHROPIC_BASE_URL="https://api.novita.ai/anthropic"
export ANTHROPIC_AUTH_TOKEN="<Novita API Key>"
export ANTHROPIC_MODEL="moonshotai/kimi-k2-instruct"
export ANTHROPIC_SMALL_FAST_MODEL="moonshotai/kimi-k2-instruct"

4.Starting Claude Code

With installation and configuration complete, you can now start Claude Code in your project directory. Navigate to your desired project location using the cd command:

cd <your-project-directory>
claude .

The dot (.) parameter instructs Claude Code to operate in the current directory. Upon startup, you’ll see the Claude Code prompt appear in an interactive session.

This indicates the tool is ready to receive your instructions. The interface provides a clean, intuitive environment for natural language programming interactions.

5.Building Your First Project

Claude Code excels at transforming detailed project descriptions into functional applications. After entering your prompt, press Enter to begin the task. Claude Code will analyze your requirements, create the necessary files, implement the functionality, and provide a complete project structure with documentation.

Conclusion

Kimi K2 is the best choice for AI agents that need strong reasoning, complex tool use, lower price, and open-source flexibility. If your agent must handle complex tasks, multiple languages, or needs full control and customization, Kimi K2 is ideal.

GPT-4o is better when you need the fastest responses, multimodal capabilities, or easy integration—especially for English-based, real-time applications and if budget is not a main concern.

In summary:

• Choose Kimi K2 for advanced, cost-effective, and customizable agents.
• Choose GPT-4o for speed, multimodal tasks, and simple setup.

Frequently Asked Questions

Novita AI is the All-in-one cloud platform that empowers your AI ambitions. Integrated APIs, serverless, GPU Instance — the cost-effective tools you need. Eliminate infrastructure, start free, and make your AI vision a reality.

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