Developer-First Payment Protocol

Commerce without middlemen

Accept crypto payments with 0% transaction fees and instant settlement. Built on HTTP 402 + Solana. Production-ready.

Install SDK View Documentation
0%
Transaction Fees
400ms
Settlement Time
127+
Active Merchants
~/cart402-demo
1import { Cart402 } from '@cart402/sdk'
2
3const cart = new Cart402({
4 shopify: { store: 'store.myshopify.com' },
5 wallet: process.env.MERCHANT_WALLET
6})
7
8await cart.addProduct('prod-123', 2)
9const result = await cart.checkout().pay()
10// ✓ Payment confirmed in 412ms
400ms
$0
Average Annual Savings
$38,247
+127%
Transactions Today
1,247
Avg. Settlement
392ms

Built for developers.
Optimized for commerce.

Everything you need to accept crypto payments

01

Zero Transaction Fees

Keep 100% of your revenue. Only pay blockchain fees (~$0.0001 per transaction).

Stripe 2.9% + $0.30
CART402 $0.0001
02

Instant Settlement

Funds available in ~400ms. No 2-7 day wait for bank transfers.

Payment
0ms
Confirmed
400ms
Stripe
2-7 days
03

No Chargebacks

Crypto payments are final. Zero fraud risk, zero disputes.

0
Chargeback Risk
04

TypeScript Native

Full type safety, autocomplete, and compile-time validation.

const cart: Cart402 = { total: 299.99, status: 'confirmed' }
05

Global Payments

Accept payments from anywhere. No geo-restrictions or compliance headaches.

06

Production Ready

Battle-tested in production. Comprehensive docs and 24/7 support.

99.9% Uptime 24/7 Support

Simple API. Powerful features.

INIT Initialize
POST Add Product
POST Checkout
POST Process Payment
implementation.ts
response.json
import { Cart402 } from '@cart402/sdk'

const cart = new Cart402({
  shopify: {
    store: 'mystore.myshopify.com',
    apiKey: process.env.SHOPIFY_API_KEY
  },
  wallet: process.env.MERCHANT_WALLET
})

Ready to eliminate payment fees?

Join 127+ merchants saving thousands monthly

Get Started View Documentation