WebSocket market data streaming API

Why use WebSocket

• Updates are pushed as prices change, which is more timely than polling REST on a timer and does not use your per-minute request allowance.
• One connection can subscribe to many symbols, and several connections can subscribe to the same symbol without affecting each other.
• The protocol matches the official iTick API, so existing subscription code only needs a new endpoint.

Message format

// Subscribe / unsubscribe. types: tick, quote, depth, kline@1
{"ac":"subscribe","params":"AAPL$US,700$HK","types":"quote,tick"}
{"ac":"unsubscribe","params":"AAPL$US","types":"quote"}

// Heartbeat
{"ac":"ping","params":"1731688569840"}

// Pushed message
{"code":1,"data":{"s":"BTCUSDT","r":"BA","ld":83988.54,"v":0.00019,"type":"tick"}}

JavaScript example

const ws = new WebSocket("wss://itick.dev/crypto?token=YOUR_API_KEY");

ws.onopen = () => {
  ws.send(JSON.stringify({ ac: "subscribe", params: "BTCUSDT$BA", types: "quote,tick" }));
  // Send a heartbeat at least every 30 seconds
  setInterval(() => ws.send(JSON.stringify({ ac: "ping", params: String(Date.now()) })), 25000);
};

ws.onmessage = (event) => console.log(event.data);

Supported markets

Connect to wss://itick.dev/{market} where market is stock, forex, crypto, indices, future or fund. Available data depends on your plan.

Connection and subscription limits

Concurrent connections per API key per market and symbols per connection are set by your plan; see pricing. The free plan does not include WebSocket by default.

Frequently asked questions