X
x402
Payment-Gated APIs on Stacks

Give a credit card
to your agent

Enable AI agents and applications to pay for API access with cryptocurrency. Monetize your endpoints with micropayments in STX.

server.ts
import { x402PaymentRequired, STXtoMicroSTX } from 'x402-stacks';

app.get(
  '/api/premium-data',
  x402PaymentRequired({
    amount: STXtoMicroSTX(0.001), // 0.001 STX
    address: process.env.SERVER_ADDRESS,
    network: 'testnet',
    facilitatorUrl: process.env.FACILITATOR_URL,
  }),
  (req, res) => {
    res.json({ data: 'Premium content' });
  }
);

Built for the future of AI

x402 enables autonomous agents to pay for resources, unlocking new possibilities for AI-driven applications.

💳

Micropayments

Accept payments as low as fractions of STX. Perfect for pay-per-use models and AI agent transactions.

Simple Integration

Drop-in middleware for Express.js. Add payment gates to your APIs with just a few lines of code.

🔒

Tiered Pricing

Dynamic pricing based on request parameters, user tiers, or resource types. Maximize revenue potential.

🎯

Rate Limiting

Offer free requests up to a limit, then require payment. Perfect for freemium models.

🤖

AI Agent Ready

Designed for autonomous agents. Enable your AI to pay for resources and services independently.

🔐

Custom Validation

Implement custom payment validation logic. Check allowlists, minimum amounts, or other business rules.

Ready to monetize your APIs?

Start accepting cryptocurrency payments for your API endpoints today.