What is x402?
x402 is an open, neutral standard for internet-native payments. It revives the HTTP 402 "Payment Required" status code—originally defined but rarely used—to enable instant, programmatic payments between clients and servers.
How it works
- Client requests a resource from the server
- If payment is required, server responds with HTTP 402 and payment instructions
- Client sends payment (e.g. stablecoins) and retries
- Server verifies payment and returns the resource
Key benefits
- Zero protocol fees — Only network fees, no percentage cuts
- Zero wait — Money moves at the speed of the internet
- Zero friction — No accounts or personal information needed
- Zero centralization — Anyone can build on or extend x402
Use cases
Monetize APIs, microservices, digital content paywalls, proxy services, and pay-per-request models. Ideal for AI agents that need to autonomously pay for services.