Claude API:
Powerful AI Reasoning & Conversation
Easily integrate the full Claude model lineup through OpenAI-compatible and Anthropic native formats. Supports Extended Thinking, Tool Use, multimodal input, streaming—pay as you go, with prices as low as 20% of the official rate.
Why use Claude through Ace Data Cloud?
Anthropic's Claude is one of the most powerful AI models available today, excelling at reasoning, programming, mathematics, and creative writing. However, using the Anthropic API directly may involve high prices and strict rate limits.
Ace Data Cloud provides a complete Claude API proxy service at prices as low as 20% of the official rate, along with an OpenAI-compatible format—allowing you to switch from OpenAI to Claude without modifying any code, or use both simultaneously.
All Claude API Features
A complete API suite covering all Claude capabilities, with two interface formats to choose from
OpenAI-Compatible Format
Use Claude through the /v1/chat/completions interface, fully compatible with the OpenAI SDK. Switch from GPT to Claude without modifying your code.
Anthropic Native Messages
Use Anthropic's native format through the /v1/messages interface, with full support for all Claude-specific features, including Extended Thinking.
Extended Thinking
Enable Claude's deep reasoning mode—the model performs structured thinking before answering, significantly improving performance on complex reasoning, math, and programming tasks.
Tool Use / Function Calling
Let Claude call tools and functions you define. Both formats support the full tool-calling specification for building powerful AI Agents.
Multimodal Input
Supports combined image + text input. Claude can analyze images, read document screenshots, and understand charts—no additional OCR calls required.
Streaming
Both formats support SSE streaming, returning generated content in real time. Both the Chat Completions and Messages APIs can use stream: true.
from openai import OpenAI
client = OpenAI(
api_key="YOUR_API_KEY",
base_url="https://api.acedata.cloud/v1"
)
response = client.chat.completions.create(
model="claude-sonnet-4-20250514",
messages=[
{"role": "system", "content": "你是一个有帮助的助手。"},
{"role": "user", "content": "解释量子计算的基本原理"}
],
stream=True
)
for chunk in response:
if chunk.choices[0].delta.content:
print(chunk.choices[0].delta.content, end="")
{
"id": "chatcmpl-abc123",
"object": "chat.completion",
"model": "claude-sonnet-4-20250514",
"choices": [{
"index": 0,
"message": {
"role": "assistant",
"content": "量子计算利用量子力学的..."
},
"finish_reason": "stop"
}],
"usage": {
"prompt_tokens": 28,
"completion_tokens": 256,
"total_tokens": 284
}
}
Switch with the OpenAI SDK in One Line of Code
Simply replace base_url and model to use Claude in your existing OpenAI project—no code refactoring required.
Get an API Key
Register with Ace Data Cloud and obtain a Bearer Token from the console
Modify base_url
Set base_url to https://api.acedata.cloud/v1
Select a Claude Model
Change the model parameter to any Claude model name, such as claude-sonnet-4-20250514
Two API formats, choose as needed
OpenAI-compatible format enables seamless switching, while Anthropic's native format unlocks all capabilities
| Feature | Chat Completions | Messages API |
|---|---|---|
| Endpoint | /v1/chat/completions |
/v1/messages |
| OpenAI SDK compatibility | ✓ | ✗ |
| Anthropic SDK compatibility | ✗ | ✓ |
| Streaming | ✓ | ✓ |
| Tool Use / Function Calling | ✓ | ✓ |
| Multimodal input (Vision) | ✓ | ✓ |
| Extended Thinking | ✗ | ✓ |
| Token counting | ✗ | ✓ |
| System Prompt | ✓ (messages array) | ✓ (separate system field) |
What Can You Build with the Claude API?
From intelligent conversations to complex reasoning—developers are building these applications with Claude
AI Conversational Assistants
Build intelligent customer service, personal assistants, or knowledge Q&A systems with Claude's exceptional language understanding and generation capabilities
Programming Assistance
Code generation, review, debugging, and refactoring. Claude excels at programming tasks and supports all major languages
Data Analysis
Document parsing, data extraction, and report generation. Multimodal input enables Claude to analyze charts and screenshots directly
AI Agent
Build autonomous agents and automated workflows with Tool Use. Claude can call APIs, query databases, and perform complex tasks
Get Started in 3 Quick Steps
From registration to sending your first Claude message, it takes less than 3 minutes
Register and Get an API Key
Create a free account on Ace Data Cloud and generate your Bearer Token from the console.
Choose an API Format
Use OpenAI-compatible Chat Completions for quick integration, or use Anthropic's native Messages API to unlock all features.
Start a Conversation
Send your first message and experience Claude's powerful reasoning capabilities. Streaming is supported for real-time responses.
Why choose Ace Data Cloud instead of using Anthropic directly?
Comprehensive advantages in pricing, rate limits, and compatibility
| Comparison | Ace Data Cloud | Direct Anthropic Connection |
|---|---|---|
| Pricing | As low as 20% of the official price | Official pricing |
| Rate Limits | ✓ Ample concurrency quota | ✗ Strict limits (Tier-dependent) |
| OpenAI-Compatible Format | ✓ | ✗ |
| Anthropic Native Format | ✓ | ✓ |
| Extended Thinking | ✓ | ✓ |
| Tool Use | ✓ | ✓ |
| Available Worldwide | ✓ Ready to use out of the box | ✗ Restricted in some regions |
| Pay as You Go | ✓ Flexible top-ups | Monthly billing |
| Claude Code Integration | ✓ | ✓ |
Choose the Right Model Family
From lightweight and fast to top-tier reasoning—Claude offers multi-tier model options
Haiku Family
High Speed, Low CostThe fastest response speed and lowest cost. Ideal for simple tasks, high-concurrency scenarios, and latency-sensitive applications.
- ✓ Claude 3 Haiku / Claude 3.5 Haiku
- ✓ Claude Haiku 4.5 (Latest)
- ✓ Millisecond-level response speed
- ✓ The lowest-cost Claude model
- ✓ Ideal for classification, extraction, and simple Q&A
Sonnet Family
Best Balanced ChoiceThe best balance of performance and cost. Ideal for most production-grade applications, combining excellent reasoning capabilities with reasonable pricing.
- ✓ Claude 3.5 Sonnet / Claude 3.7 Sonnet
- ✓ Claude Sonnet 4 / Claude Sonnet 4.5 (Latest)
- ✓ Excellent coding and reasoning capabilities
- ✓ Supports Extended Thinking
- ✓ The most popular choice among developers
Fable / Opus Family
FlagshipClaude Fable 5.1 is the latest flagship for long-horizon agents and complex reasoning, while the older Fable 5 and Opus families continue to cover high-intensity analytical tasks.
- ✓ Claude Fable 5.1 (Latest flagship, 1 million Token context, maximum output 128K Token)
- ✓ Claude Fable 5 (Retained for compatibility)
- ✓ Claude 3 Opus / Opus 4 / Opus 4.1
- ✓ Claude Opus 5.5 (Messages API, 1 million Token context, maximum output 128K Token)
- ✓ Claude Opus 4.5 / Opus 4.6 / Opus 4.7 / Opus 4.8
- ✓ The strongest reasoning and analytical capabilities
- ✓ Supports Extended Thinking
- ✓ Ideal for research, complex programming, and in-depth analysis
Claude API Pricing
Charged by Token usage, with prices as low as 20% of Anthropic's official rates. No subscription fees, no hidden charges.
Volume plans offer additional discounts
Charged based on actual Token usage, with separate pricing for input and output
- ✓ Haiku series: lowest-cost entry point
- ✓ Sonnet series: the best value choice
- ✓ Opus series: flagship reasoning capabilities
- ✓ Supports all 28+ model variants
- ✓ Extended Thinking Tokens at the same price
- ✓ Streaming — free
- ✓ Token counting — free
Dedicated plans for high-volume teams
- ✓ Usage-based tiered discounts
- ✓ Priority support and account manager
- ✓ Custom rate limits
- ✓ SLA guarantee
- ✓ Private deployment options
Frequently Asked Questions
Everything you need to know about using the Claude API
What is the difference from using the Anthropic API directly? ▾
Ace Data Cloud is a proxy service for the Anthropic Claude API. We provide exactly the same Claude models and capabilities, but at prices as low as 20% of the official price, with additional support for the OpenAI-compatible format. Your requests are ultimately processed by Anthropic's Claude models, with exactly the same quality.
Do you support the OpenAI SDK? ▾
Yes! Our Chat Completions API is fully compatible with the OpenAI SDK (Python, Node.js, Go, etc.). Simply change base_url to https://api.acedata.cloud/v1 and set model to the Claude model name. Your existing OpenAI code requires almost no changes.
Which Claude models are supported? ▾
We support the latest Claude Fable 5.1, the legacy-compatible Fable 5, as well as the Haiku, Sonnet, and Opus model families. Fable 5.1 is designed for the most complex long-horizon reasoning and agent tasks, supporting 1 million Token context and up to 128K Token output; the other families cover different scenarios ranging from low latency to intensive analysis.
What is Extended Thinking? ▾
Extended Thinking is Claude's deep reasoning mode. When enabled, the model goes through a structured thinking process before answering, similar to how humans “think before speaking.” This significantly improves performance on tasks such as mathematics, logical reasoning, and complex programming. Enable it through the thinking parameter of the Messages API, or directly use a model name with the -thinking suffix.
Can it be used with Claude Code? ▾
Yes! Ace Data Cloud's Claude API can directly provide backend support for Claude Code. Simply set the API base URL and Token in the Claude Code configuration to use it, and enjoy prices as low as 20% of the official price along with ample concurrency limits. See our Claude Code configuration guide for details.
How does pricing work? ▾
Billing is based on Token usage, with input Tokens and output Tokens priced separately. Prices vary by model—Haiku is the cheapest, while Opus is the most expensive. No subscription fees or monthly fees; pay only for what you use. Available immediately after top-up, and your balance never expires. Bulk packages offer further discounts.
Are there rate limits? ▾
Compared with Anthropic's strict rate limits for new accounts (which require gradually increasing your Tier), Ace Data Cloud provides much more generous concurrency capacity. You do not need to worry about being rate-limited during peak hours, nor do you need to prepay substantial fees to increase your Tier.
Is multimodal input supported? ▾
Yes. Both the Chat Completions and Messages APIs support combined image + text input. You can include Base64-encoded images or image URLs in messages, and Claude will understand the image content and respond in combination with the text. JPEG, PNG, GIF, and WebP formats are supported.
Other AI Models
Explore our complete AI API suite, covering images, video, music, search, and more
Get Started with the Claude API Now
Join thousands of developers using the full Claude model lineup at prices as low as 20% of the official rate. Pay as you go—no subscription fees, no commitment.