The Micropayment Showdown: x402 vs. MPP

Web3 & BlockchainFinTech

In the world of micropayments, two competing visions are vying for dominance: x402 and MPP. But which one is right for your business?

TL;DR
• x402 is a protocol for micropayments that uses HTTP 402 and is led by Coinbase.
• MPP is a protocol for high-frequency transactions that uses sessions and is led by Stripe and Tempo.
• Both protocols aim to make payments as lightweight as HTTP requests.

Summary
HTTP 402, once a dormant status code, now powers two competing micropayment protocols that let machines buy data and services over HTTP. Stripe’s dual support for Coinbase’s x402 and Tempo’s MPP offers merchants a choice between minimal, open‑source payments and a stack‑ready solution that streamlines agent transactions, integrates with existing dashboards, and scales from indie APIs to enterprise marketplaces.
• x402 turns an HTTP 402 response into a payment request with no accounts or keys.
• MPP uses session‑based streaming to batch micropayments and avoid per‑request blockchain overhead.
• Stripe’s Agentic Commerce Suite unifies both protocols under a single fraud, tax, and reporting stack.
• Early volume is modest, but the infrastructure backing both protocols is robust.

x402 is a lightweight shim that turns an HTTP 402 response into a payment request. The server returns the cost, token, and chain; the client pays on‑chain, attaches a proof, and retries. No accounts, keys, or subscriptions are required. Stripe’s integration exposes a middleware that generates deposit addresses, monitors on‑chain events, and settles into the merchant’s Stripe balance. The protocol is open‑source under Apache 2.0 and currently supports USDC on Base, with plans for Polygon and Solana and other emerging chains.

MPP introduces session‑based streaming payments to avoid a blockchain transaction per request. An agent authorizes a spending limit once; subsequent calls are charged against that limit and settled in bulk. Tempo’s custom L1 processes tens of thousands of transactions per second with sub‑second finality and no native gas token, using stablecoins for fees. Stripe’s Shared Payment Tokens let agents forward a buyer’s card or wallet credentials securely, scoped to a single transaction, enabling hybrid fiat‑crypto flows without exposing sensitive data.

Stripe’s Agentic Commerce Suite sits atop both protocols, allowing merchants to upload catalogs, select target agents, and rely on Stripe’s fraud, tax, and reporting engines. Existing merchants can switch to MPP or x402 without re‑platforming; the integration paths are separate, so the choice of protocol does not affect the core PaymentIntents API. The strategy is to own the abstraction layer while letting the underlying rails compete, ensuring that settlements always land in Stripe balances today.

Early adoption remains modest; x402 has processed 50 million transactions via Agentic Wallets, but daily volume averages $28 000 with $0.20 payments, largely testing activity. MPP’s directory lists over 100 services, including Anthropic, DoorDash, and Shopify, yet merchant counts are low and most traffic is experimental. Despite the small scale, the infrastructure backing both protocols—Stripe’s $1.9 trillion 2025 volume, Coinbase, Cloudflare, Visa, and Tempo’s partner network—provides a robust foundation for future growth in.

The choice between x402 and MPP ultimately depends on the specific needs of your business. Consider the trade-offs between simplicity, scalability, and compliance when making your decision.