x402 explained: how a web server charges per request

x402 is an open, Apache-2.0 payment standard that uses the HTTP 402 Payment Required status code, so a server can charge for an API or content without accounts or logins. The client pays, retries the request and gets the resource. Using it does not mean anyone earns. docs

How a payment works

1. The client asks for a resource.
2. The server replies 402 Payment Required, with its payment requirements in a PAYMENT-REQUIRED header. GitHub
3. The client picks one option, builds a payment payload and retries with a PAYMENT-SIGNATURE header. GitHub
4. The server checks it, either itself or through a facilitator's /verify endpoint, then settles through /settle. docs GitHub
5. If it all holds, the server returns 200 OK with the resource and a PAYMENT-RESPONSE receipt header. GitHub

If the client already knows the price, steps 1 and 2 can be skipped. GitHub

Who gets paid

The seller, meaning whoever runs the server. The standard itself has "0 fees built in". docs A facilitator or network may still charge, so read your provider's terms. Buyers can be developers or AI agents. docs

Facilitators

A facilitator is an optional third party that verifies and settles payments. A server can also do both itself. The public x402.org facilitator is for testnet and quickstarts, not default mainnet production. GitHub

Payment schemes

Source: GitHub

What it does not tell you

Not the meme token that shares the ticker. And a working paywall is not revenue: someone still has to want what is behind it. When a drop names an x402 earner, we tag the figure as checked, estimated, claimed or not given. See how we check and do AI agents make money.

Sources: x402 docs (https://docs.x402.org/), x402 on GitHub (https://github.com/x402-foundation/x402). Checked 31 October 2026.

Try it: x402 endpoint checker. Related: x402, MCP server, AI agent that earns. Research and education, not advice: see Not financial advice.

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