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Why use x402 with your client

x402 standardizes how clients discover payment requirements, construct payment payloads, and complete on-chain payments for HTTP resources. Benefits include: ✅ Customers don’t pay network fees.
✅ Merchants don’t pay network fees.
✅ Payment settles in < 1 second.
✅ Universal compatibility — if it speaks HTTP, it speaks x402.

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Architecture at a glance

x402 sequence diagram
  • Client (buyer): Calls protected resources and constructs payment payloads.
  • Server: Advertises payment requirements, verifies/settles payments, fulfills requests.
  • Facilitator: Verifies and/or settles payments for the resource server.
  • Blockchains: Execute and confirm payments.

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Getting started

Select one of the quickstart examples, or read the reference for more details.

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x402 reference

For a deeper dive into message shapes, headers, verification and settlement responses, see the x402 Reference.

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