Cardano has officially been integrated into the x402 software development kit (SDK), allowing apps and AI agents to make payments using ADA and Cardano Native Tokens (CNTs) through API calls. The Cardano Foundation announced the update on its X account, stating that the agent economy can now utilize Cardano as a payment rail with x402.
x402 open HTTP payments standard
x402 is an open HTTP payment standard originally developed by Coinbase and now managed by the Linux Foundation. The protocol addresses the previously unused HTTP 402 status code, enabling web services to require a payment per request. This system allows applications and AI agents to pay with stablecoins or other cryptocurrencies without the need for accounts, API keys, or traditional checkout pages.
The Cardano Foundation, a non-profit organization focused on advancing Cardano’s adoption and ecosystem development, became an Associate Member of the x402 initiative under the Linux Foundation in July 2026. Other notable x402 members include Visa, Mastercard, Stripe, Google, AWS, and Coinbase.
This collaboration positions Cardano among major payment network operators, reflecting its ambitions to expand into mainstream payment infrastructure.
Mini dictionary: x402, an open HTTP payments protocol designed to enable microtransactions over the web with cryptocurrency (including stablecoins and ADA), reviving the HTTP 402 status code for per-request payments with no need for user accounts, API keys, or checkout pages.
Cardano’s integration and expanded payment utility
The latest update means that any application or AI agent using the x402 SDK can pay for API requests in ADA or any supported Cardano Native Token. This process does not require prior registration, API keys, or completing payment checkouts, streamlining the transaction process for developers and service providers.
Cardano Foundation stated on X, “Any app or AI agent can pay for an API call in ADA or any CNT over a web request.”
Additionally, the payment functionality is now available as working code within the x402 repository. This includes client, server, facilitator, and end-to-end examples, confirming Cardano’s actual implementation beyond specification only.
Industry partnerships and scalability milestone
The Cardano Foundation has recently joined Mastercard’s Crypto Partner Program under its Blockchain track. Through this initiative, Cardano is expected to engage with Mastercard and other participants in areas such as payments, stablecoins, cross-border money movement, business-to-business (B2B) transactions, and settlement processes.
In a separate scalability development, Cardano’s Ouroboros Leios team demonstrated a performance increase to about 1,000 transactions per second (TPS). A recent demonstration featured a Leios node reaching 250 TxkB/s, which equates to roughly 1,000 straightforward Cardano transactions each second. By comparison, the current Cardano mainnet processes up to 4.5 TxkB/s.
| Network | Current Throughput | Leios Demo Throughput |
|---|---|---|
| Cardano Mainnet | 4.5 TxkB/s | 250 TxkB/s |
| Estimated TPS | ~18 TPS* | ~1,000 TPS |
*Assuming an average transaction size of around 0.25 kB.
