Testnet Models
Base Sepolia
Developer testing with testnet USDC. No real money required.
Available Testnet Models
2 models
GPT-OSS 20B
openaiTestnetOpen-weight 20B model (Apache 2.0), similar performance to o3-mini. Available on testnet for developer testing.
Price: $0.0010/request
GPT-OSS 120B
openaiTestnetOpen-weight 120B model (Apache 2.0), flagship open model. Available on testnet for developer testing.
Price: $0.0020/request
Getting Started
- Get testnet ETH from the Base Sepolia faucet
- Get testnet USDC from the Circle USDC faucet
- Configure your SDK to use
https://testnet.blockrun.ai/api - Start testing with the models above
Code Examples
Python
from blockrun_llm import LLMClient
# Use testnet API endpoint
client = LLMClient(api_url="https://testnet.blockrun.ai/api")
# Chat with testnet model (uses testnet USDC on Base Sepolia)
response = client.chat("openai/gpt-oss-120b", "Hello!")
print(response)TypeScript
import { LLMClient } from '@blockrun/llm';
// Use testnet API endpoint
const client = new LLMClient({
apiUrl: 'https://testnet.blockrun.ai/api'
});
// Chat with testnet model (uses testnet USDC on Base Sepolia)
const response = await client.chat('openai/gpt-oss-120b', 'Hello!');
console.log(response);cURL
curl -X POST https://testnet.blockrun.ai/api/v1/chat/completions \
-H "Content-Type: application/json" \
-H "PAYMENT-SIGNATURE: <payment_header>" \
-d '{
"model": "openai/gpt-oss-120b",
"messages": [{"role": "user", "content": "Hello!"}],
"max_tokens": 1024
}'Network Configuration
Network
Base Sepolia
Chain ID
84532
USDC Contract
0x036CbD53842c5426634e7929541eC2318f3dCF7e
API Endpoint
https://testnet.blockrun.ai