The OKX API empowers developers, traders, and algorithmic systems to interact seamlessly with one of the world’s leading digital asset exchanges. Whether you're building a high-frequency trading bot or monitoring real-time market movements, the OKX WebSocket API delivers fast, reliable, and secure access to live data and trading functions.
This guide dives deep into the core features of the OKX WebSocket API—covering public and private channels, connection setup, authentication, and real-time trading operations—so you can build robust, responsive applications that leverage live exchange data.
🔧 Supported APIs
OKX provides a powerful WebSocket API that enables direct, two-way communication between your application and the exchange server. Unlike REST APIs that require repeated polling, WebSockets maintain a persistent connection for instant updates.
👉 Discover how real-time data can transform your trading strategy
The WebSocket API supports:
- Real-time market data streaming (tickers, order books, trades)
- Instant notifications for account activity
- Fast order placement and management
- Live position tracking
This makes it ideal for algorithmic traders, quantitative analysts, and fintech developers who demand speed and precision.
🌐 Public vs. Private WebSocket Channels
WebSocket channels on OKX are categorized into public and private, each serving distinct purposes based on user authentication status.
Public Channels
These channels broadcast market data accessible to all users without authentication. They are perfect for monitoring price movements and market depth.
Available public channels include:
- Ticker channel: Real-time price summary for instruments
- K-Line channel: Candlestick chart data at various intervals
- Order book channel: Live bid/ask levels (depth)
- Mark price channel: Fair value pricing to prevent manipulation
- Trades channel: Recent executed trades
No login is required—ideal for dashboards, price alerts, or market analysis tools.
Private Channels
These require authenticated access using an API key and are tied to your personal account activity.
Private channels include:
- Account channel: Balance updates and margin changes
- Order channel: Order status changes (new, filled, canceled)
- Position channel: Position size, entry price, PnL updates
These are essential for active traders managing live portfolios or running automated strategies.
👉 Unlock real-time private channel access in minutes
🔐 Authentication & Connection Setup
To use private channels or execute trades via WebSocket, you must authenticate using three credentials:
- API Key: Generated from your OKX account settings
- API Secret: A confidential key used to sign requests
- Passphrase: A custom string set during API key creation
Additionally, two configuration flags control behavior:
IsDemo: Set totrueto connect to the OKX demo (testnet) environmentIsPrivate: Enable to subscribe to private account/order/position channels
Establishing a Connection
Once configured, your client connects to OKX’s WebSocket server. Upon successful connection, the OnOKXConnect event fires. If an error occurs, OnOKXError returns detailed diagnostics.
Here's a basic connection example in Delphi-like pseudocode:
oClient := TsgcWebSocketClient.Create(nil);
oOKX := TsgcWSAPI_OKX.Create(nil);
oOKX.Client := oClient;
oOKX.OKX.ApiKey := 'alsdjk23kandfnasbdfdkjhsdf';
oOKX.OKX.ApiSecret := 'aldskjfk3jkadknfajndsjfj23j';
oOKX.OKX.Passphrase := 'secret_passphrase';
oClient.Active := True;
procedure OnOKXConnect(Sender: TObject; aMessage, aCode, aRawMessage: string);
begin
DoLog('#OKX Connected');
end;
procedure OnOKXError(Sender: TObject; aCode, aMessage, aRawMessage: string);
begin
DoLog('#error: ' + aMessage);
end;After connecting, you can begin subscribing to channels and sending trading commands.
📈 Subscribing to Public Channels
After establishing a connection, you can immediately subscribe to public market data feeds. For example, to receive instrument details for futures markets:
procedure OnOKXConnect(Sender: TObject; aMessage, aCode, aRawMessage: string);
begin
oOKX.SubscribeInstruments(okxitFutures);
end;This enables real-time updates on available trading pairs, contract specifications, funding rates, and more—perfect for building dynamic trading interfaces or pre-trade analysis tools.
🔒 Accessing Private Channels
To monitor your account or manage orders in real time, enable IsPrivate and authenticate with your API credentials.
Example: Subscribe to futures order updates for BTC-USD contracts:
procedure OnOKXConnect(Sender: TObject; aMessage, aCode, aRawMessage: string);
begin
oOKX.SubscribeOrders(okxitFutures, 'BTC-USD', 'BTC-USD-200329');
end;You’ll receive instant notifications when orders are placed, modified, filled, or canceled—critical for low-latency trading systems.
💹 Executing Trades via WebSocket
Trading through the WebSocket API requires authentication and follows strict parameter rules to ensure clarity and security.
Key Order Parameters
| Parameter | Required | Description |
|---|---|---|
id | Yes | Client-generated message ID (up to 32 chars) |
instId | Yes | Instrument ID (e.g., BTC-USD-SWAP) |
tdMode | Yes | Trade mode: cross, isolated, or cash |
side | Yes | buy or sell |
ordType | Yes | Order type: market, limit, post_only, etc. |
sz | Yes | Quantity to trade |
px | Optional | Price (required for limit orders) |
Other advanced options include reducing positions only (reduceOnly), banning amendments (banAmend), and specifying quote/base currency for spot market orders (tgtCcy).
Place Orders
Examples of placing market and limit orders:
// Place Market Order
TsgcWSAPI_OKX1.PlaceMarketOrder(okxosBuy, 'ETH-BTC', 1);
// Place Limit Order
TsgcWSAPI_OKX1.PlaceLimitOrder(okxosBuy, 'ETH-BTC', 1, 0.25);Cancel & Amend Orders
Manage open orders dynamically:
// Cancel an order
TsgcWSAPI_OKX1.CancelOrder('ETH-BTC', '457589362405027840');
// Amend order size (e.g., change quantity to 2)
TsgcWSAPI_OKX1.AmendOrder('ETH-BTC', '457589362405027840', '', 2);These capabilities allow fine-grained control over trade execution—especially valuable in volatile markets.
❓ Frequently Asked Questions (FAQ)
What is the difference between public and private WebSocket channels?
Public channels provide real-time market data like prices and trades without requiring login. Private channels deliver personalized data such as account balances and order updates but require API authentication.
Do I need an API key to use the OKX WebSocket?
An API key is only required for private channels and trading functions. Public data streaming works without authentication.
Can I use the WebSocket API for automated trading bots?
Yes. The OKX WebSocket API is widely used for algorithmic trading due to its low latency and real-time event-driven architecture.
How do I generate an API key on OKX?
Log in to your OKX account, go to Settings > API Management, create a new key, and securely store the Key, Secret, and Passphrase.
Is there a test environment for development?
Yes. Use the IsDemo flag to connect to the OKX demo (paper trading) environment and test strategies risk-free.
What programming languages support the OKX WebSocket API?
While OKX provides official documentation in JSON format, developers have implemented clients in Python, JavaScript, C#, Delphi, Java, and more using standard WebSocket libraries.
✅ Final Thoughts
The OKX WebSocket API is a cornerstone tool for modern crypto traders and developers. With real-time data feeds across public and private channels—and the ability to place, cancel, and amend orders at lightning speed—it unlocks powerful opportunities for automation and precision trading.
Whether you're analyzing market trends or deploying live strategies, integrating with OKX’s WebSocket infrastructure gives you a competitive edge in today’s fast-moving digital asset markets.