✦ Crypto payment gateway

Accept crypto payments in JavaScript at 0.1%

Integrate the Zeno API in JavaScript and ship a working crypto checkout in around 20 lines of code, at a flat 0.1% per transaction with instant on-chain settlement.

Why JavaScript developers choose Zeno

The Unified Crypto Infrastructure Built for Your Stack

Maximize Your Margins

Our 0.1% fee per transaction puts around 3% back on your net margin compared with card-processor APIs charging between 1.5% and 3%.

Native JavaScript SDK

A simple, developer-friendly JavaScript API. Easy to integrate, easy to use.

Unified Chain Access

One API covers every major stablecoin, token and chain, including USDT on Tron, USDC on Base, PYUSD on Solana, and BTC on Bitcoin and Lightning Network.

What you can build with Zeno in JavaScript

Custom storefronts

Build a custom checkout flow in JavaScript that handles payment creation, redirect, webhook verification, and order fulfilment, without the constraints of pre-built plugins.

SaaS billing

Add crypto payments to your JavaScript SaaS application alongside card billing, with one-time and recurring patterns supported through the same API.

Marketplace flows

Handle crypto payments between buyers and sellers on a marketplace built in JavaScript, with automated payouts, escrow patterns, and split payments.

API integrations

Layer crypto payments into existing JavaScript platforms (CMSs, ecommerce frameworks, internal tools) without changing the underlying stack.

API reference for JavaScript developers

The three core endpoints handle the complete payment flow:

Endpoint	Method	Purpose
/checkouts	POST	Create a new checkout and get a payment URL
/checkouts/{id}	GET	Query the status of an existing checkout
Webhook (Your endpoint)	POST (incoming)	Receive signed webhooks when payments confirm

Authentication uses the X-API-Key header with your store key (prefixed sk_). Webhook signatures use HMAC-SHA256 against your webhook secret.

FAQs

Everything you need to know before getting started

How long does the JavaScript integration take?

Most teams ship a working crypto checkout in an afternoon. The fastest path is to call the create-checkout endpoint and wire up a signed webhook handler, which typically runs to 20 to 50 lines of JavaScript code.

What authentication does the API use?

Zeno uses API key authentication through the X-API-Key header. Keys are prefixed with sk_ and scoped to your store. Rotation is handled from the dashboard, and IP whitelisting is available for stricter deployments.

How do webhook signatures work in JavaScript?

Each webhook delivery includes a signature header. Your JavaScript handler verifies the signature against your webhook secret using HMAC-SHA256, which confirms the event came from Zeno and hasn't been tampered with.

How does Zeno handle errors and retries?

The API returns standard HTTP status codes with JSON error bodies. Webhook delivery retries automatically with exponential backoff if your endpoint returns a non-2xx response, which gives your JavaScript handler resilience against transient failures.

Ship your first crypto checkout in JavaScript today

Integrate the Zeno API in JavaScript and ship a working checkout this afternoon at a flat 0.1% per transaction.

Team

Hugo Pino — founder of the Zeno Bank

The only time I leave my house is to go to the gym

Built a decentralized exchange that reached $27M in deposits.

I got a UAE Golden Visa for my work in Web3