The x402 protocol is an open payment standard built on HTTP, designed to enable machine-to-machine transactions. Launched by Coinbase in May 2025, it utilizes the long-dormant HTTP 402 Payment Required status code to facilitate automated payments for APIs and AI agents using stablecoins.
The protocol operates as a set of rules rather than a blockchain or token. It primarily uses USDC on the Base network for settlement, though it supports other chains including Solana, Polygon, and Arbitrum. Facilitators handle onchain verification, allowing agents to pay without holding native gas tokens.
In April 2026, the Linux Foundation announced the formation of the x402 Foundation, which became fully operational on July 14, 2026. Michael Hursta was appointed executive director on October 1, 2026. The foundation currently oversees the protocol with 57 member organizations, including Google, Visa, and Mastercard.
Adoption metrics show that x402 processed over 196 million transactions across 12 chains by November 1, 2026, with a total settlement value exceeding $42 million. In October 2026 alone, the protocol handled 5.1 million transactions worth approximately $274,000.
Despite its growth, x402 faces competition from standards like the Agentic Commerce Protocol from Stripe and OpenAI, and the Trusted Agent Protocol from Visa. The protocol has no native token, and officials warn against speculative assets claiming to be associated with x402.
