In brief
- x402 is an open payment standard from Coinbase that uses the web’s long-unused HTTP 402 code to let AI agents and apps pay for online services.
- Payments are mostly made in USDC on Base and settled through facilitators, so buyers sign an authorization instead of creating accounts or API keys.
- More than 50 companies, including Visa, Mastercard and Google, have joined the x402 Foundation, which now governs the protocol under the Linux Foundation.
Nobody really built the web with payments in mind. Early HTTP specifications included a status code, 402 “Payment Required”, that was reserved for a future system of online payments. Then it sat unused for about 30 years. Payments were slow and expensive, and they needed accounts, card…
