Solana's x402 Protocol Processes $50B in AI Payments Volume

Solana's x402 protocol has processed around $50 billion in volume and connected about 150,000 merchant endpoints. This milestone gives Solana an edge in AI payments, according to a recent webinar by the Solana Foundation and Coinbase.

The x402 protocol solves three specific problems for autonomous software: open tool discovery, economic reasoning, and a single runtime where agents can both earn and spend. It achieves this by reviving an unused HTTP status code, 402 Payment Required, which allows servers to respond with pricing terms, letting AI agents evaluate the cost, authorize payment, and retry the same call with proof of payment attached.

Solana's pitch leans on its existing infrastructure: over $15 billion in circulating stablecoins, roughly $10 trillion in cumulative transfers, 400-millisecond block times, and fees near a thousandth of a cent. The x402 protocol has processed over 180 million transactions since launching about a year ago and is now referenced in the docs and workflows of Cloudflare, Stripe, and AWS.