Learn / What are machine-to-machine (M2M) payments?
What are machine-to-machine (M2M) payments?
Machine-to-machine payments are transactions where both the payer and payee are software — an AI agent paying an API, a crawler paying a website, one service metering another. They are small (often under $1), frequent (millions per day), and fully automated, which makes them structurally different from human payments.
The settlement path
A machine payment clears in five steps: the service quotes machine-readable terms (e.g. via HTTP 402); the agent's wallet pays in stablecoin; a facilitator verifies the payment; value settles on-chain in seconds; both sides get a receipt for reconciliation. Billing engines then roll micro-settlements into invoices.
Why USDC dominates
About 98.6% of machine payments settle in USDC, mostly on Base — a function of x402's defaults, deep liquidity, and regulatory clarity after the GENIUS Act. Card rails are entering via bridges (Mastercard Agent Pay, Visa Intelligent Commerce) for larger, human-sized transactions.
The economics
In one recent 30-day window x402 processed ~75M payments totaling only ~$24M — an average of ~$0.32. The value is in the metering infrastructure (facilitators, wallets, billing), not in any single transaction.
Frequently asked questions
How fast do machine payments settle?
Typically under two seconds on modern rails like Base, with network fees around $0.0001.
What is pay-per-crawl?
A machine-payment pattern where websites quote a price to bots/crawlers for access — Cloudflare and AWS CloudFront both shipped machine-readable pricing for this in 2026. See our pay-per-crawl explainer.
Can machine payments use regular bank rails?
For sub-dollar payments, no — fixed fees make them uneconomic. Banks and cards participate in the macro lane and via stablecoin issuance instead.
Live, curated, and machine-readable.
See the settlement-layer monitor