x402 Echo

Instantly test the x402 protocol for pay-per-use APIs.
Perfect for agentic and micro transactions.

Live endpoints. Real payments. 100% free.

Test your x402 client against:

Testnets

Base Sepolia

https://x402.payai.network/api/base-sepolia/paid-content

Avalanche Fuji

https://x402.payai.network/api/avalanche-fuji/paid-content

Sei Testnet

https://x402.payai.network/api/sei-testnet/paid-content

Mainnets

Base Mainnet

https://x402.payai.network/api/base/paid-content

Sei Mainnet

https://x402.payai.network/api/sei/paid-content

Quickstart Guides

Axios Quickstart

Attach the x402 interceptor to Axios and pay per request.

Fetch Quickstart

Wrap fetch with x402 to handle payments automatically.

Resources