One Key, Every Leading AI Model
OpenAI · Claude · Gemini · DeepSeek — 79+ models, fully compatible
Integrated 10+ Top-tier AI Providers
One Key. Rock Solid.
Unified API · Transparent Pricing · Intelligent Routing · Enterprise Security
Unified API, One Key
Fully compatible with OpenAI SDK. Zero code changes to access 79+ models. Integrate once, use everywhere.
Transparent Pricing, CNY Settlement
Pay-as-you-go, failed requests not billed. Alipay / WeChat supported, invoices available.
High Availability, Smart Routing
Multi-node distributed deployment, automatic failover. 99.9%+ uptime, your business never sleeps.
Data Security & Compliance
No request content storage. Zero Data Retention support. Enterprise-grade compliance standards.
Lower Price. More Models. Rock Solid.
Below Official Pricing
Bulk procurement and optimized routing cut costs, passing savings directly to developers.
Full Model Coverage
79+ models in one place. No more juggling multiple provider agreements.
CNY Settlement
Alipay, WeChat Pay, and bank transfer accepted. No foreign credit card required.
Enterprise-grade Security
ZDR zero data retention, TLS encryption, audit logs. Full compliance ready.
Price Comparison · Claude Opus
* Failed requests are not billed · Based on 30-day average
3 Steps to Start Calling
Register → Copy Code → Send Request. Less than 1 minute.
1. Register & Get Key
One-click registration in console. Generate your API key and get free credits instantly.
2. Install SDK
Python, Node.js, Java, Go — one command to install. OpenAI SDK works out of the box.
3. First API Call
Replace base_url, copy the sample code, and get a response instantly.
from openai import OpenAI
client = OpenAI(
api_key="sk-your-api-key",
base_url="https://api.onefast.ai/v1"
)
response = client.chat.completions.create(
model="gpt-4o",
messages=[
{"role": "system", "content": "You are a helpful AI assistant."},
{"role": "user", "content": "Hello, introduce yourself in one sentence."}
]
)
print(response.choices[0].message.content)import OpenAI from "openai";
const client = new OpenAI({
apiKey: "sk-your-api-key",
baseURL: "https://api.onefast.ai/v1"
});
const response = await client.chat.completions.create({
model: "gpt-4o",
messages: [
{ role: "system", content: "You are a helpful AI assistant." },
{ role: "user", content: "Hello, introduce yourself in one sentence." }
]
});
console.log(response.choices[0].message.content);curl https://api.onefast.ai/v1/chat/completions \
-H "Content-Type: application/json" \
-H "Authorization: Bearer sk-your-api-key" \
-d '{
"model": "gpt-4o",
"messages": [
{"role": "system", "content": "You are a helpful AI assistant."},
{"role": "user", "content": "Hello, introduce yourself in one sentence."}
]
}'Start From One Key
Get Started · Guides · Concepts · API Reference
Get Started
Install, configure, and make your first API call.
4 articlesGuides
Step-by-step tutorials and integration cookbooks.
6 articlesConcepts
Understand the API, routing, and billing model.
5 articlesAPI Reference
Endpoints, parameters, and code examples.
4 articlesFeatured Cookbooks
Models Available Now
New models are added within 48 hours of public availability.
grok-4.5
grok-4.5
kimi-k3
kimi-k3
claude-sonnet-4-6
claude-sonnet-4-6
Gemini 1.5 Flash
claude-opus-4-6
claude-opus-4-6
gemini-2.5-flash
gemini-2.5-flash
gemini-2.5-pro
gemini-2.5-pro
DeepSeek V3
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We provide AI coding assistants and essay grading tools for students. The previous service was expensive and unstable. After switching, stability improved significantly and bulk pricing is very competitive.
I need to test different models for research. Official APIs are either inaccessible or too expensive. This platform has full model coverage, student-friendly pricing, and OpenAI SDK works with just one line change. So convenient.
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