x402 Payment Protocol

How x402 Works

The x402 protocol enables instant, micropayments for API requests using cryptocurrency.

Send API request without payment
Receive 402 Payment Required response with payment details
Client automatically signs and submits USDC transaction on Base
Client retries request with payment proof in X-PAYMENT header
API verifies payment and returns data

Supported Libraries

Python: pip install x402-requests
JavaScript: npm install x402-axios
Go: go get go-x402
Rust: cargo add x402-rs

Benefits

No API keys or account creation required
Pay-per-use pricing (no subscriptions)
Instant settlement (~2 seconds)
Anonymous usage
Low transaction fees on Base network