Cardano has officially joined the x402 SDK, the open HTTP payment standard originally driven by Coinbase and now managed by the Linux Foundation. The Cardano Foundation announced that any application or artificial intelligence agent can now make payments in ADA or Cardano Native Tokens directly over web requests, without requiring an account, API key, or checkout page.
The integration builds on Cardano’s associate membership in x402 under the Linux Foundation since July 2026, alongside Visa, Mastercard, Stripe, Google, AWS, and Coinbase. By early September, the network’s implementation existed as functional code rather than a written specification, with client, server, facilitator, and working examples merged into the protocol repository.
The first developer release supports TypeScript, while Python support is planned. Cardano Foundation documentation says the facilitator has completed an end-to-end transaction on Cardano preprod using a real onchain transaction, but it has not yet been tested against mainnet. As a result, the current rollout remains at the infrastructure and testing stage rather than demonstrating large-scale commercial ADA payments by autonomous agents.
The x402 standard uses the HTTP “402 Payment Required” status code. When software requests a paid resource, the service returns the price, accepted asset, and payment instructions as part of the same internet request; the client signs the transaction, and a facilitator verifies and settles it. This allows AI agents to buy data, API calls, or computing capacity without accounts or subscriptions.
Cardano’s entry places ADA within the same machine-payment framework already being tested on Solana, XRP Ledger, Base, and other networks. Coinbase reported more than 100 million x402 payments across Base and Solana, while XRP Ledger has recorded over 1.4 million AI-related x402 transactions. Cardano’s current implementation provides the payment tools for developers, with mainnet deployment still a separate step.
In addition, the Cardano Foundation has joined the Mastercard Crypto Partner Program in its Blockchains area, focused on cross-border payments, B2B transactions, and settlement. Separately, developers of Ouroboros Leios demonstrated capacity of about 1,000 transactions per second, compared with current mainnet throughput of around 4.5 TxkB/s.
