The x402 Foundation

The x402 Foundation is the neutral steward of the x402 open payment standard. The canonical x402 repository now lives under the x402 Foundation organization on GitHub (github.com/x402-foundation/x402), where the specification, SDKs and reference implementations are maintained as an open standard for anyone to build on.

x402 was created and open-sourced by Coinbase. As the standard grew, the project was moved under the x402 Foundation to govern it as a neutral, multi-stakeholder open standard. The original coinbase/x402 repository is now a development fork that feeds into the Foundation repo.

x402 originated at Coinbase but is explicitly designed as a neutral, open standard — it is not tied to any single company or network. Development now happens in the open under the x402 Foundation organization, and anyone can contribute new networks, schemes or implementations under the project’s contribution criteria.

The canonical repository is github.com/x402-foundation/x402. The protocol specification lives in the specs/ directory, with reference SDKs published under the @x402/* npm namespace (plus Python and Go implementations). The whitepaper is available at x402.org.

Read the specification and contribution guide in the Foundation repo, join the open development on GitHub, or simply start building — return HTTP 402 from your endpoint and settle payments through a facilitator. You can also explore the 1.2k x402 projects we track to see what others are building.