> For the complete documentation index, see [llms.txt](https://docs.usexpay.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.usexpay.xyz/learn-more/why-x402.md).

# Why x402?

x402 is the native protocol for machine-to-machine payments. It brings a standard 402 Payment Required flow to HTTP, enabling per-request payments that are fast, composable, and easy for agents to use.

#### Benefits (from our landing narrative)

* Built for the agent economy: AI agents can pay per call without accounts or subscriptions
* No integration friction: replaces key juggling and billing backends with a single HTTP header
* Composable infrastructure: x402-wrapped endpoints become programmable building blocks
* Future-proof standard: a simple, widely adoptable payment rail for autonomous systems

#### How xPay uses x402

* Every paid proxy call passes through Faremeter x402 middleware
* Payments verify before forwarding the request; successful responses trigger earnings tracking
* Marketplace and MCP layers sit on top, enabling discovery and agent-native consumption

#### Learn more about x402

Read the [x402 official documentation](https://x402.org/)


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