Guide · Updated 2026
x402 vs Stripe MPP: which should you use in 2026?
Two systems woke up the same idea: let machines pay over the web using HTTP 402 Payment Required.
x402 came from Coinbase in 2025 and is now an open standard under the x402 Foundation. MPP (Machine Payments Protocol) launched March 18, 2026 from Stripe and Tempo.
They solve a similar problem. They are not the same tool. This guide is a practical decision aid, not a standards document.
Quick comparison
| x402 | MPP | |
|---|---|---|
| Style | Open protocol | Stripe + Tempo system |
| Payments | Mostly crypto / stablecoins | Crypto plus cards, wallets, and more |
| Billing shape | Pay per request | Pay per request, or open a session and stream many tiny payments |
| Best for | Agents, micropayments, open APIs | High-volume sessions, hybrid fiat, teams already on Stripe |
| Lock-in | Low | Higher (Stripe ecosystem) |
Choose x402 if you want
- Tiny payments that would die under card fees
- Buyers who do not need an account
- An open setup you can host yourself
- Solana or Base stablecoin settlement
Choose MPP if you want
- Session-style spending (authorize a budget, then use it fast)
- Fiat and crypto in one flow
- Stripe fraud tools, refunds, and reporting
- Enterprise-friendly compliance defaults
Can you use both?
Yes. Some products use x402 for open agent traffic and Stripe or MPP for human or enterprise buyers. That is a normal split, not a contradiction. Stripe also participates in the broader x402 ecosystem, which is another signal this is convergence more than a holy war.
Simple rule
Micropayments and open agent access: start with x402.
High-frequency sessions and card rails: start with MPP.
Still unsure: prototype x402 on Solana devnet in an afternoon, then decide with real numbers.