Brief Overview

• x402 is an open payment standard launched by Coinbase. It utilizes the long-unused HTTP 402 status code to enable AI proxies and applications to make payments for online services.
• Payments are mostly completed through USDC on the Base network, and settlement is carried out via intermediary services. Therefore, what the buyer signs is a payment authorization, rather than a creation of an account or a API key.
• More than 50 companies, including Visa, Mastercard, and Google, have joined x402 Foundation. The foundation is currently responsible for protocol governance under Linux Foundation.

In fact, payment was not truly considered a core aspect in the initial design of the Internet. In the early HTTP specifications, there was a status code – 402 “Payment Required (Payment required)”, which was originally reserved for future online payment systems. For about the next 30 years, this status code was never actually used. The payment process was slow and costly, and it required accounts, bank card information, as well as intermediaries capable of canceling transactions. None of these factors were suitable for small-value payments initiated by software.

Today, this gap has become even more important, as AI proxies begin to browse web pages for users, invoke API, and purchase services. A single proxy cannot fill out payment forms or register for monthly subscriptions for each tool it uses. Cloudflare indicates that nowadays, over half of internet traffic comes from non-human users, and claims that their network sees 1 billion HTTP 402 responses every day.

x402 attempts to ultimately provide a native payment method for the internet. This article introduces what it is, how it works, who its supporters are, and whether there are any related tokens.

Do you know?

The status code 402 “Payment Required (payment required)” has existed in the HTTP standard since the 1990s. At that time, it was marked as “to be used in the future,” and x402 was the first attempt to truly implement it on a large scale.

What is x402?

x402 is an open payment standard built upon HTTP. HTTP is a protocol for transmitting data over the internet. In May 2025, Coinbase was launched together with partners such as AWS, Anthropic, Circle, and NEAR to create x402. It allows API, applications, and AI agents to pay service fees in stablecoins within regular web page requests.

x402 is not blockchain, nor is it a type of token. It is a set of rules that include message formats, request headers, and a request-response process that can be followed by any server or client. Payments mostly use USDC, which is a stablecoin issued by Circle and pegged to the US dollar; the Ethereum layer-2 network of Coinbase serves as the main settlement chain. However, this protocol is theoretically adaptable to any chain and currently also supports networks such as Solana, Polygon, Arbitrum, as well as traditional bank card payments.

On April 2, 2026, Linux Foundation announced the launch of x402 and Foundation. Coinbase contributed to this protocol, while companies such as Microsoft, Google, Visa, and Mastercard expressed their initial support. The new x402 and Foundation were fully operational on July 14, 2026, and are currently responsible for governing this protocol under a framework that remains neutral to various manufacturers.

How does x402 work?

x402 operates through a brief handshake process within a single ordinary web page request:

• Request:The proxy or application requests a certain item from the server, such as a API call, a dataset, or an article.
• 402 Response:The server responded with "402 Payment Required", along with machine-readable terms including the price, which tokens are accepted, and the payment wallet address.
• Payment:The client signs the payment authorization with its own wallet, then sends the request again, attaching that signature to the request header.
• Delivery:The server checks the payment, completes the on-chain settlement, and returns the requested content.

Most of the work on the blockchain is completed by “intermediaries” ( facilitator ). These services are responsible for verifying payments and settling them on the blockchain, so sellers do not need to set up their own encrypted payment infrastructure. On the EVM blockchain, x402 uses EIP-3009, which is a standard that allows users to transfer tokens by signing authorizations, without having to send transactions directly themselves. This means that buyers do not need to hold ETH to pay the Gas fee.

What is the special thing about x402?

The core selling point of x402 is the ultra-small amount payments initiated by machines. The settlement on Base takes only a few seconds, and the cost is far less than 1 cent, making it reasonable to charge a fraction of a cent for each API payment. Users do not need to register, do not need to manage API keys, nor do they need to subscribe. Agents simply need to make a payment and then obtain the requested service.

Its adoption has been growing rapidly. In December 2025, x402 was released, which introduced a new identity mechanism based on wallets, allowing agents to avoid re-payment with each call. It also added automatic service discovery and support for more chains. In May 2026, x402 added a batch settlement feature, enabling agents to submit signed credentials to sellers for unified batch settlement. According to data cited in Fireblocks from tracker and agenteconomy.to, as of November 1, 2026, x402 had processed over 196 million transactions across 12 chains, with a total settlement amount exceeding 42 million US dollars. Coinbase indicates that in the second quarter of 2026, over 97% of on-chain agent transactions used x402.

However, it is worth noting that, according to Fireblocks, more than half of the historical cumulative transactions for x402 came from a frenzy that lasted for two months at the end of 2025. During that time, traders ran automated scripts to mint and sell tokens PING issued through x402. Since then, the level of activity has significantly declined: in October 2026, x402 processed 5.1 million transactions, amounting to approximately $274,000.

Who is cooperating with x402?

• Cloudflare:One of the co-developers of x402 and Foundation is Coinbase, with the other two being Stripe and Cloudflare. Cloudflare has already supported x402 within its Agents SDK and provides a monetization gateway that runs at the network edge.
• Stripe:The co-developers and senior members of x402 and Foundation can convert payments made in x402 to their standard PaymentIntents, allowing merchants to receive reports they are familiar with and payments settled in conventional currencies.
• Agentic.Market:Coinbase launched an open market in April 2026, which is used to discover and compare x402 services, and provides real-time price and trading volume data.
• CoinGecko:Provides a pay-per-use encryption market data API interface for agents to call.
• AWS:Its AgentCore service manages proxy payments, budgets, and permissions on the buyer's side.
• Google:Its proxy-to-proxy (A2A) x402 extension is part of (AP2), and it is jointly constructed by (Google) with (Coinbase), (Ethereum Foundation), and (MetaMask). (x402) is used to complete the encrypted settlement between proxies.

x402 Does it have a token?

No. x402 is a protocol, not a cryptocurrency, and it does not have an official native token. Payments are made using existing stablecoins, mainly USDC. There have been some speculative “x402” tokens that have appeared on different chains in the market, but Coinbase, x402, and Foundation have not issued or supported these tokens. Any project that claims to be the official x402 token should be treated with great caution.

Where to purchase USDC for payment of x402

To use x402, a proxy or application requires a wallet that holds supported stablecoins on the supported networks, typically USDC on Base. USDC is widely available on mainstream exchanges such as Coinbase, Kraken, and Binance. Coinbase allows users to send USDC directly to Base. Developers can also use the Coinbase Developer Platform wallet or Circle Wallets to fund proxies and set expenditure limits in order to control their behavior.

The Future of x402

x402 and Foundation are rapidly expanding. When it officially commenced operations in July 2026, it had 40 member organizations; since then, the list of members has grown to 57, including Visa, Mastercard, American Express, PayPal, Google, Shopify, Circle, Stripe, and AWS. Michael Hursta took on the role of executive director for the foundation on October 1, 2026.

However, x402 is not the only option. The open standards Agentic Commerce Protocol developed by Stripe and OpenAI, as well as Trusted Agent Protocol from Visa, are all vying for a place in the field of proxy payments. Despite this, Stripe and Visa are also senior members of x402 and Foundation.

Stripe also jointly developed Machine Payments Protocol with the payment blockchain Tempo. Similar to x402, MPP also uses the HTTP 402 status code to have proxies make payments on behalf of services, but it has added a session-based billing method that allows proxies to use the service while making payments, eliminating the need for each request to be settled on the blockchain.

Since June 2026, it has also supported x402 payments. One of the biggest open questions is whether the vast number of x402 transactions will translate into sustained, real commercial activity. If so, then this payment status code, which has been idle for 30 years, could ultimately handle a large portion of the payment traffic in the AI economy.