CCXT for TypeScript/JavaScript

A comprehensive guide to using CCXT in TypeScript and JavaScript projects for cryptocurrency exchange integration.

Installation

REST API (Standard CCXT)

npm install ccxt

WebSocket API (Real-time, ccxt.pro)

npm install ccxt

Both REST and WebSocket APIs are included in the same package.

Quick Start

REST API - TypeScript

import ccxt from 'ccxt'

const exchange = new ccxt.binance()
await exchange.loadMarkets()
const ticker = await exchange.fetchTicker('BTC/USDT')
console.log(ticker)

REST API - JavaScript (CommonJS)

const ccxt = require('ccxt')

(async () => {
    const exchange = new ccxt.binance()
    await exchange.loadMarkets()
    const ticker = await exchange.fetchTicker('BTC/USDT')
    console.log(ticker)
})()

WebSocket API - Real-time Updates

import ccxt from 'ccxt'

const exchange = new ccxt.pro.binance()
while (true) {
    const ticker = await exchange.watchTicker('BTC/USDT')
    console.log(ticker)  // Live updates!
}
await exchange.close()

REST vs WebSocket

fetch*

watch*

ccxt.exchange()

ccxt.pro.exchange()

When to use REST:

• Placing orders
• Fetching account balance
• One-time data queries
• Order management (cancel, fetch orders)

When to use WebSocket:

• Real-time price monitoring
• Live orderbook updates
• Arbitrage detection
• Portfolio tracking with live updates

Creating Exchange Instance

REST API

// Public API (no authentication)
const exchange = new ccxt.binance({
    enableRateLimit: true  // Recommended!
})

// Private API (with authentication)
const exchange = new ccxt.binance({
    apiKey: 'YOUR_API_KEY',
    secret: 'YOUR_SECRET',
    enableRateLimit: true
})

WebSocket API

// Public WebSocket
const exchange = new ccxt.pro.binance()

// Private WebSocket (with authentication)
const exchange = new ccxt.pro.binance({
    apiKey: 'YOUR_API_KEY',
    secret: 'YOUR_SECRET'
})

// Always close when done
await exchange.close()

Common REST Operations

Loading Markets

// Load all available trading pairs
await exchange.loadMarkets()

// Access market information
const btcMarket = exchange.market('BTC/USDT')
console.log(btcMarket.limits.amount.min)  // Minimum order amount

Fetching Ticker

// Single ticker
const ticker = await exchange.fetchTicker('BTC/USDT')
console.log(ticker.last)      // Last price
console.log(ticker.bid)       // Best bid
console.log(ticker.ask)       // Best ask
console.log(ticker.volume)    // 24h volume

// Multiple tickers (if supported)
const tickers = await exchange.fetchTickers(['BTC/USDT', 'ETH/USDT'])

Fetching Order Book

// Full orderbook
const orderbook = await exchange.fetchOrderBook('BTC/USDT')
console.log(orderbook.bids[0])  // [price, amount]
console.log(orderbook.asks[0])  // [price, amount]

// Limited depth
const orderbook = await exchange.fetchOrderBook('BTC/USDT', 5)  // Top 5 levels

Creating Orders

Limit Order

// Buy limit order
const order = await exchange.createLimitBuyOrder('BTC/USDT', 0.01, 50000)
console.log(order.id)

// Sell limit order
const order = await exchange.createLimitSellOrder('BTC/USDT', 0.01, 60000)

// Generic limit order
const order = await exchange.createOrder('BTC/USDT', 'limit', 'buy', 0.01, 50000)

Market Order

// Buy market order
const order = await exchange.createMarketBuyOrder('BTC/USDT', 0.01)

// Sell market order
const order = await exchange.createMarketSellOrder('BTC/USDT', 0.01)

// Generic market order
const order = await exchange.createOrder('BTC/USDT', 'market', 'sell', 0.01)

Fetching Balance

const balance = await exchange.fetchBalance()
console.log(balance.BTC.free)   // Available balance
console.log(balance.BTC.used)   // Balance in orders
console.log(balance.BTC.total)  // Total balance

Fetching Orders

// Open orders
const openOrders = await exchange.fetchOpenOrders('BTC/USDT')

// Closed orders
const closedOrders = await exchange.fetchClosedOrders('BTC/USDT')

// All orders (open + closed)
const allOrders = await exchange.fetchOrders('BTC/USDT')

// Single order by ID
const order = await exchange.fetchOrder(orderId, 'BTC/USDT')

Fetching Trades

// Recent public trades
const trades = await exchange.fetchTrades('BTC/USDT', undefined, 10)

// Your trades (requires authentication)
const myTrades = await exchange.fetchMyTrades('BTC/USDT')

Canceling Orders

// Cancel single order
await exchange.cancelOrder(orderId, 'BTC/USDT')

// Cancel all orders for a symbol
await exchange.cancelAllOrders('BTC/USDT')

WebSocket Operations (Real-time)

Watching Ticker (Live Price Updates)

const exchange = new ccxt.pro.binance()

while (true) {
    const ticker = await exchange.watchTicker('BTC/USDT')
    console.log(ticker.last, ticker.timestamp)
}

await exchange.close()

Watching Order Book (Live Depth Updates)

const exchange = new ccxt.pro.binance()

while (true) {
    const orderbook = await exchange.watchOrderBook('BTC/USDT')
    console.log('Best bid:', orderbook.bids[0])
    console.log('Best ask:', orderbook.asks[0])
}

await exchange.close()

Watching Trades (Live Trade Stream)

const exchange = new ccxt.pro.binance()

while (true) {
    const trades = await exchange.watchTrades('BTC/USDT')
    for (const trade of trades) {
        console.log(trade.price, trade.amount, trade.side)
    }
}

await exchange.close()

Watching Your Orders (Live Order Updates)

const exchange = new ccxt.pro.binance({
    apiKey: 'YOUR_API_KEY',
    secret: 'YOUR_SECRET'
})

while (true) {
    const orders = await exchange.watchOrders('BTC/USDT')
    for (const order of orders) {
        console.log(order.id, order.status, order.filled)
    }
}

await exchange.close()

Watching Balance (Live Balance Updates)

const exchange = new ccxt.pro.binance({
    apiKey: 'YOUR_API_KEY',
    secret: 'YOUR_SECRET'
})

while (true) {
    const balance = await exchange.watchBalance()
    console.log('BTC:', balance.BTC)
    console.log('USDT:', balance.USDT)
}

await exchange.close()

Watching Multiple Symbols

const exchange = new ccxt.pro.binance()
const symbols = ['BTC/USDT', 'ETH/USDT', 'SOL/USDT']

while (true) {
    // Watch all symbols concurrently
    const tickers = await exchange.watchTickers(symbols)
    for (const symbol in tickers) {
        console.log(symbol, tickers[symbol].last)
    }
}

await exchange.close()

Complete Method Reference

Market Data Methods

Tickers & Prices

• fetchTicker(symbol)

  - Fetch ticker for one symbol

• fetchTickers([symbols])

  - Fetch multiple tickers at once

• fetchBidsAsks([symbols])

  - Fetch best bid/ask for multiple symbols

• fetchLastPrices([symbols])

  - Fetch last prices

• fetchMarkPrices([symbols])

  - Fetch mark prices (derivatives)

Order Books

• fetchOrderBook(symbol, limit)

  - Fetch order book

• fetchOrderBooks([symbols])

  - Fetch multiple order books

• fetchL2OrderBook(symbol)

  - Fetch level 2 order book

• fetchL3OrderBook(symbol)

  - Fetch level 3 order book (if supported)

Trades

• fetchTrades(symbol, since, limit)

  - Fetch public trades

• fetchMyTrades(symbol, since, limit)

  - Fetch your trades (auth required)

• fetchOrderTrades(orderId, symbol)

  - Fetch trades for specific order

OHLCV (Candlesticks)

• fetchOHLCV(symbol, timeframe, since, limit)

  - Fetch candlestick data

• fetchIndexOHLCV(symbol, timeframe)

  - Fetch index price OHLCV

• fetchMarkOHLCV(symbol, timeframe)

  - Fetch mark price OHLCV

• fetchPremiumIndexOHLCV(symbol, timeframe)

  - Fetch premium index OHLCV

Account & Balance

• fetchBalance()

  - Fetch account balance (auth required)

• fetchAccounts()

  - Fetch sub-accounts

• fetchLedger(code, since, limit)

  - Fetch ledger history

• fetchLedgerEntry(id, code)

  - Fetch specific ledger entry

• fetchTransactions(code, since, limit)

  - Fetch transactions

• fetchDeposits(code, since, limit)

  - Fetch deposit history

• fetchWithdrawals(code, since, limit)

  - Fetch withdrawal history

• fetchDepositsWithdrawals(code, since, limit)

  - Fetch both deposits and withdrawals

Trading Methods

Creating Orders

• createOrder(symbol, type, side, amount, price, params)

  - Create order (generic)

• createLimitOrder(symbol, side, amount, price)

  - Create limit order

• createMarketOrder(symbol, side, amount)

  - Create market order

• createLimitBuyOrder(symbol, amount, price)

  - Buy limit order

• createLimitSellOrder(symbol, amount, price)

  - Sell limit order

• createMarketBuyOrder(symbol, amount)

  - Buy market order

• createMarketSellOrder(symbol, amount)

  - Sell market order

• createMarketBuyOrderWithCost(symbol, cost)

  - Buy with specific cost

• createStopLimitOrder(symbol, side, amount, price, stopPrice)

  - Stop-limit order

• createStopMarketOrder(symbol, side, amount, stopPrice)

  - Stop-market order

• createStopLossOrder(symbol, side, amount, stopPrice)

  - Stop-loss order

• createTakeProfitOrder(symbol, side, amount, takeProfitPrice)

  - Take-profit order

• createTrailingAmountOrder(symbol, side, amount, trailingAmount)

  - Trailing stop

• createTrailingPercentOrder(symbol, side, amount, trailingPercent)

  - Trailing stop %

• createTriggerOrder(symbol, side, amount, triggerPrice)

  - Trigger order

• createPostOnlyOrder(symbol, side, amount, price)

  - Post-only order

• createReduceOnlyOrder(symbol, side, amount, price)

  - Reduce-only order

• createOrders([orders])

  - Create multiple orders at once

• createOrderWithTakeProfitAndStopLoss(symbol, type, side, amount, price, tpPrice, slPrice)

  - OCO order

Managing Orders

• fetchOrder(orderId, symbol)

  - Fetch single order

• fetchOrders(symbol, since, limit)

  - Fetch all orders

• fetchOpenOrders(symbol, since, limit)

  - Fetch open orders

• fetchClosedOrders(symbol, since, limit)

  - Fetch closed orders

• fetchCanceledOrders(symbol, since, limit)

  - Fetch canceled orders

• fetchOpenOrder(orderId, symbol)

  - Fetch specific open order

• fetchOrdersByStatus(status, symbol)

  - Fetch orders by status

• cancelOrder(orderId, symbol)

  - Cancel single order

• cancelOrders([orderIds], symbol)

  - Cancel multiple orders

• cancelAllOrders(symbol)

  - Cancel all orders for symbol

• editOrder(orderId, symbol, type, side, amount, price)

  - Modify order

Margin & Leverage

• fetchBorrowRate(code)

  - Fetch borrow rate for margin

• fetchBorrowRates([codes])

  - Fetch multiple borrow rates

• fetchBorrowRateHistory(code, since, limit)

  - Historical borrow rates

• fetchCrossBorrowRate(code)

  - Cross margin borrow rate

• fetchIsolatedBorrowRate(symbol, code)

  - Isolated margin borrow rate

• borrowMargin(code, amount, symbol)

  - Borrow margin

• repayMargin(code, amount, symbol)

  - Repay margin

• fetchLeverage(symbol)

  - Fetch leverage

• setLeverage(leverage, symbol)

  - Set leverage

• fetchLeverageTiers(symbols)

  - Fetch leverage tiers

• fetchMarketLeverageTiers(symbol)

  - Leverage tiers for market

• setMarginMode(marginMode, symbol)

  - Set margin mode (cross/isolated)

• fetchMarginMode(symbol)

  - Fetch margin mode

Derivatives & Futures

Positions

• fetchPosition(symbol)

  - Fetch single position

• fetchPositions([symbols])

  - Fetch all positions

• fetchPositionsForSymbol(symbol)

  - Fetch positions for symbol

• fetchPositionHistory(symbol, since, limit)

  - Position history

• fetchPositionsHistory(symbols, since, limit)

  - Multiple position history

• fetchPositionMode(symbol)

  - Fetch position mode (one-way/hedge)

• setPositionMode(hedged, symbol)

  - Set position mode

• closePosition(symbol, side)

  - Close position

• closeAllPositions()

  - Close all positions

Funding & Settlement

• fetchFundingRate(symbol)

  - Current funding rate

• fetchFundingRates([symbols])

  - Multiple funding rates

• fetchFundingRateHistory(symbol, since, limit)

  - Funding rate history

• fetchFundingHistory(symbol, since, limit)

  - Your funding payments

• fetchFundingInterval(symbol)

  - Funding interval

• fetchSettlementHistory(symbol, since, limit)

  - Settlement history

• fetchMySettlementHistory(symbol, since, limit)

  - Your settlement history

Open Interest & Liquidations

• fetchOpenInterest(symbol)

  - Open interest for symbol

• fetchOpenInterests([symbols])

  - Multiple open interests

• fetchOpenInterestHistory(symbol, timeframe, since, limit)

  - OI history

• fetchLiquidations(symbol, since, limit)

  - Public liquidations

• fetchMyLiquidations(symbol, since, limit)

  - Your liquidations

Options

• fetchOption(symbol)

  - Fetch option info

• fetchOptionChain(code)

  - Fetch option chain

• fetchGreeks(symbol)

  - Fetch option greeks

• fetchVolatilityHistory(code, since, limit)

  - Volatility history

• fetchUnderlyingAssets()

  - Fetch underlying assets

Fees & Limits

• fetchTradingFee(symbol)

  - Trading fee for symbol

• fetchTradingFees([symbols])

  - Trading fees for multiple symbols

• fetchTradingLimits([symbols])

  - Trading limits

• fetchTransactionFee(code)

  - Transaction/withdrawal fee

• fetchTransactionFees([codes])

  - Multiple transaction fees

• fetchDepositWithdrawFee(code)

  - Deposit/withdrawal fee

• fetchDepositWithdrawFees([codes])

  - Multiple deposit/withdraw fees

Deposits & Withdrawals

• fetchDepositAddress(code, params)

  - Get deposit address

• fetchDepositAddresses([codes])

  - Multiple deposit addresses

• fetchDepositAddressesByNetwork(code)

  - Addresses by network

• createDepositAddress(code, params)

  - Create new deposit address

• fetchDeposit(id, code)

  - Fetch single deposit

• fetchWithdrawal(id, code)

  - Fetch single withdrawal

• fetchWithdrawAddresses(code)

  - Fetch withdrawal addresses

• fetchWithdrawalWhitelist(code)

  - Fetch whitelist

• withdraw(code, amount, address, tag, params)

  - Withdraw funds

• deposit(code, amount, params)

  - Deposit funds (if supported)

Transfer & Convert

• transfer(code, amount, fromAccount, toAccount)

  - Internal transfer

• fetchTransfer(id, code)

  - Fetch transfer info

• fetchTransfers(code, since, limit)

  - Fetch transfer history

• fetchConvertCurrencies()

  - Currencies available for convert

• fetchConvertQuote(fromCode, toCode, amount)

  - Get conversion quote

• createConvertTrade(fromCode, toCode, amount)

  - Execute conversion

• fetchConvertTrade(id)

  - Fetch convert trade

• fetchConvertTradeHistory(code, since, limit)

  - Convert history

Market Info

• fetchMarkets()

  - Fetch all markets

• fetchCurrencies()

  - Fetch all currencies

• fetchTime()

  - Fetch exchange server time

• fetchStatus()

  - Fetch exchange status

• fetchBorrowInterest(code, symbol, since, limit)

  - Borrow interest paid

• fetchLongShortRatio(symbol, timeframe, since, limit)

  - Long/short ratio

• fetchLongShortRatioHistory(symbol, timeframe, since, limit)

  - L/S ratio history

WebSocket Methods (ccxt.pro)

All REST methods have WebSocket equivalents with

watch*

Real-time Market Data

• watchTicker(symbol)

  - Watch single ticker

• watchTickers([symbols])

  - Watch multiple tickers

• watchOrderBook(symbol)

  - Watch order book updates

• watchOrderBookForSymbols([symbols])

  - Watch multiple order books

• watchTrades(symbol)

  - Watch public trades

• watchOHLCV(symbol, timeframe)

  - Watch candlestick updates

• watchBidsAsks([symbols])

  - Watch best bid/ask

Real-time Account Data (Auth Required)

• watchBalance()

  - Watch balance updates

• watchOrders(symbol)

  - Watch your order updates

• watchMyTrades(symbol)

  - Watch your trade updates

• watchPositions([symbols])

  - Watch position updates

• watchPositionsForSymbol(symbol)

  - Watch positions for symbol

Authentication Required

Methods marked with 🔒 require API credentials:

• All

  create*

  methods (creating orders, addresses)
• All

  cancel*

  methods (canceling orders)
• All

  edit*

  methods (modifying orders)
• All

  fetchMy*

  methods (your trades, orders)

• fetchBalance

  ,

  fetchLedger

  ,

  fetchAccounts

• withdraw

  ,

  transfer

  ,

  deposit

• Margin/leverage methods
• Position methods

• watchBalance

  ,

  watchOrders

  ,

  watchMyTrades

  ,

  watchPositions

Checking Method Availability

Not all exchanges support all methods. Check before using:

// Check if method is supported
if (exchange.has['fetchOHLCV']) {
    const candles = await exchange.fetchOHLCV('BTC/USDT', '1h')
}

// Check multiple capabilities
console.log(exchange.has)
// {
//   fetchTicker: true,
//   fetchOHLCV: true,
//   fetchMyTrades: true,
//   fetchPositions: false,
//   ...
// }

Method Naming Convention

• fetch*

  - REST API methods (HTTP requests)

• watch*

  - WebSocket methods (real-time streams)

• create*

  - Create new resources (orders, addresses)

• cancel*

  - Cancel existing resources

• edit*

  - Modify existing resources

• set*

  - Configure settings (leverage, margin mode)

• *Ws

  suffix - WebSocket variant (some exchanges)

Proxy Configuration

CCXT supports HTTP, HTTPS, and SOCKS proxies for both REST and WebSocket connections.

Setting Proxy

// HTTP Proxy
exchange.httpProxy = 'http://your-proxy-host:port'

// HTTPS Proxy  
exchange.httpsProxy = 'https://your-proxy-host:port'

// SOCKS Proxy
exchange.socksProxy = 'socks://your-proxy-host:port'

// Proxy with authentication
exchange.httpProxy = 'http://user:pass@proxy-host:port'

Proxy for WebSocket

WebSocket connections also respect proxy settings:

exchange.httpsProxy = 'https://proxy:8080'
// WebSocket connections will use this proxy

Testing Proxy Connection

exchange.httpProxy = 'http://localhost:8080'
try {
    await exchange.fetchTicker('BTC/USDT')
    console.log('Proxy working!')
} catch (error) {
    console.error('Proxy connection failed:', error)
}

WebSocket-Specific Methods

Some exchanges provide WebSocket variants of REST methods for faster order placement and management. These use the

*Ws

Trading via WebSocket

Creating Orders:

• createOrderWs

  - Create order via WebSocket (faster than REST)

• createLimitOrderWs

  - Create limit order via WebSocket

• createMarketOrderWs

  - Create market order via WebSocket

• createLimitBuyOrderWs

  - Buy limit order via WebSocket

• createLimitSellOrderWs

  - Sell limit order via WebSocket

• createMarketBuyOrderWs

  - Buy market order via WebSocket

• createMarketSellOrderWs

  - Sell market order via WebSocket

• createStopLimitOrderWs

  - Stop-limit order via WebSocket

• createStopMarketOrderWs

  - Stop-market order via WebSocket

• createStopLossOrderWs

  - Stop-loss order via WebSocket

• createTakeProfitOrderWs

  - Take-profit order via WebSocket

• createTrailingAmountOrderWs

  - Trailing stop via WebSocket

• createTrailingPercentOrderWs

  - Trailing stop % via WebSocket

• createPostOnlyOrderWs

  - Post-only order via WebSocket

• createReduceOnlyOrderWs

  - Reduce-only order via WebSocket

Managing Orders:

• editOrderWs

  - Edit order via WebSocket

• cancelOrderWs

  - Cancel order via WebSocket (faster than REST)

• cancelOrdersWs

  - Cancel multiple orders via WebSocket

• cancelAllOrdersWs

  - Cancel all orders via WebSocket

Fetching Data:

• fetchOrderWs

  - Fetch order via WebSocket

• fetchOrdersWs

  - Fetch orders via WebSocket

• fetchOpenOrdersWs

  - Fetch open orders via WebSocket

• fetchClosedOrdersWs

  - Fetch closed orders via WebSocket

• fetchMyTradesWs

  - Fetch your trades via WebSocket

• fetchBalanceWs

  - Fetch balance via WebSocket

• fetchPositionWs

  - Fetch position via WebSocket

• fetchPositionsWs

  - Fetch positions via WebSocket

• fetchPositionsForSymbolWs

  - Fetch positions for symbol via WebSocket

• fetchTradingFeesWs

  - Fetch trading fees via WebSocket

When to Use WebSocket Methods

Use

*Ws

• You need faster order placement (lower latency)
• You're already connected via WebSocket
• You want to reduce REST API rate limit usage
• Trading strategies require sub-100ms latency

Use REST methods when:

• You need guaranteed execution confirmation
• You're making one-off requests
• The exchange doesn't support the WebSocket variant
• You need detailed error responses

Example: Order Placement Comparison

REST API (slower, more reliable):

const order = await exchange.createOrder('BTC/USDT', 'limit', 'buy', 0.01, 50000)

WebSocket API (faster, lower latency):

const order = await exchange.createOrderWs('BTC/USDT', 'limit', 'buy', 0.01, 50000)

Checking WebSocket Method Availability

Not all exchanges support WebSocket trading methods:

if (exchange.has['createOrderWs']) {
    // Exchange supports WebSocket order creation
    const order = await exchange.createOrderWs('BTC/USDT', 'limit', 'buy', 0.01, 50000)
} else {
    // Fall back to REST
    const order = await exchange.createOrder('BTC/USDT', 'limit', 'buy', 0.01, 50000)
}

Authentication

Setting API Keys

// During instantiation
const exchange = new ccxt.binance({
    apiKey: 'YOUR_API_KEY',
    secret: 'YOUR_SECRET',
    enableRateLimit: true
})

// After instantiation
exchange.apiKey = 'YOUR_API_KEY'
exchange.secret = 'YOUR_SECRET'

Environment Variables (Recommended)

const exchange = new ccxt.binance({
    apiKey: process.env.BINANCE_API_KEY,
    secret: process.env.BINANCE_SECRET,
    enableRateLimit: true
})

Testing Authentication

try {
    const balance = await exchange.fetchBalance()
    console.log('Authentication successful!')
} catch (error) {
    if (error instanceof ccxt.AuthenticationError) {
        console.error('Invalid API credentials')
    }
}

Error Handling

Exception Hierarchy

BaseError
├─ NetworkError (recoverable - retry)
│  ├─ RequestTimeout
│  ├─ ExchangeNotAvailable
│  ├─ RateLimitExceeded
│  └─ DDoSProtection
└─ ExchangeError (non-recoverable - don't retry)
   ├─ AuthenticationError
   ├─ InsufficientFunds
   ├─ InvalidOrder
   └─ NotSupported

Basic Error Handling

import ccxt from 'ccxt'

try {
    const ticker = await exchange.fetchTicker('BTC/USDT')
} catch (error) {
    if (error instanceof ccxt.NetworkError) {
        console.error('Network error - retry:', error.message)
    } else if (error instanceof ccxt.ExchangeError) {
        console.error('Exchange error - do not retry:', error.message)
    } else {
        console.error('Unknown error:', error)
    }
}

Specific Exception Handling

try {
    const order = await exchange.createOrder('BTC/USDT', 'limit', 'buy', 0.01, 50000)
} catch (error) {
    if (error instanceof ccxt.InsufficientFunds) {
        console.error('Not enough balance')
    } else if (error instanceof ccxt.InvalidOrder) {
        console.error('Invalid order parameters')
    } else if (error instanceof ccxt.RateLimitExceeded) {
        console.error('Rate limit hit - wait before retrying')
        await exchange.sleep(1000)  // Wait 1 second
    } else if (error instanceof ccxt.AuthenticationError) {
        console.error('Check your API credentials')
    }
}

Retry Logic for Network Errors

async function fetchWithRetry(maxRetries = 3) {
    for (let i = 0; i < maxRetries; i++) {
        try {
            return await exchange.fetchTicker('BTC/USDT')
        } catch (error) {
            if (error instanceof ccxt.NetworkError && i < maxRetries - 1) {
                console.log(`Retry ${i + 1}/${maxRetries}`)
                await exchange.sleep(1000 * (i + 1))  // Exponential backoff
            } else {
                throw error
            }
        }
    }
}

Rate Limiting

Built-in Rate Limiter (Recommended)

const exchange = new ccxt.binance({
    enableRateLimit: true  // Automatically throttles requests
})

Manual Delays

await exchange.fetchTicker('BTC/USDT')
await exchange.sleep(1000)  // Wait 1 second
await exchange.fetchTicker('ETH/USDT')

Checking Rate Limit

console.log(exchange.rateLimit)  // Milliseconds between requests

Common Pitfalls

Forgetting

await

// Wrong - returns Promise, not data
const ticker = exchange.fetchTicker('BTC/USDT')
console.log(ticker.last)  // ERROR: ticker is a Promise!

// Correct
const ticker = await exchange.fetchTicker('BTC/USDT')
console.log(ticker.last)  // Works!

Using REST for Real-time Monitoring

// Wrong - wastes rate limits, slow
while (true) {
    const ticker = await exchange.fetchTicker('BTC/USDT')  // REST
    console.log(ticker.last)
    await exchange.sleep(1000)
}

// Correct - use WebSocket
const exchange = new ccxt.pro.binance()
while (true) {
    const ticker = await exchange.watchTicker('BTC/USDT')  // WebSocket
    console.log(ticker.last)
}

Not Closing WebSocket Connections

// Wrong - memory leak
const exchange = new ccxt.pro.binance()
const ticker = await exchange.watchTicker('BTC/USDT')
// Forgot to close!

// Correct
const exchange = new ccxt.pro.binance()
try {
    while (true) {
        const ticker = await exchange.watchTicker('BTC/USDT')
        console.log(ticker)
    }
} finally {
    await exchange.close()
}

Multiple Instances with Same API Keys

// Wrong - nonce conflicts
const ex1 = new ccxt.binance({ apiKey: 'key', secret: 'secret' })
const ex2 = new ccxt.binance({ apiKey: 'key', secret: 'secret' })
await ex1.fetchBalance()
await ex2.fetchBalance()  // May fail due to nonce issues!

// Correct - reuse single instance
const exchange = new ccxt.binance({ apiKey: 'key', secret: 'secret' })
await exchange.fetchBalance()
await exchange.fetchBalance()

Not Enabling Rate Limiter

// Wrong - may hit rate limits
const exchange = new ccxt.binance()
for (let i = 0; i < 100; i++) {
    await exchange.fetchTicker('BTC/USDT')  // May fail!
}

// Correct
const exchange = new ccxt.binance({ enableRateLimit: true })
for (let i = 0; i < 100; i++) {
    await exchange.fetchTicker('BTC/USDT')  // Automatically throttled
}

Browser Usage

Via CDN

<script src="https://cdn.jsdelivr.net/npm/ccxt@latest/dist/ccxt.browser.js"></script>
<script>
    const exchange = new ccxt.binance()
    exchange.loadMarkets().then(() => {
        return exchange.fetchTicker('BTC/USDT')
    }).then(ticker => {
        console.log(ticker)
    })
</script>

ES Modules

import ccxt from 'https://cdn.jsdelivr.net/npm/ccxt@latest/dist/ccxt.browser.js'

const exchange = new ccxt.binance()
await exchange.loadMarkets()
const ticker = await exchange.fetchTicker('BTC/USDT')
console.log(ticker)

Troubleshooting

Common Issues

1. "Cannot find module 'ccxt'"

• Solution: Run

  npm install ccxt

2. "RateLimitExceeded"

• Solution: Enable rate limiter:

  enableRateLimit: true

• Or add manual delays between requests

3. "AuthenticationError"

• Solution: Check API key and secret
• Verify API key permissions on exchange
• Check system clock is synced (use NTP)

4. "InvalidNonce"

• Solution: Sync system clock
• Use only one exchange instance per API key
• Don't run multiple bots with same credentials

5. "InsufficientFunds"

• Solution: Check available balance (

  balance.BTC.free

  )
• Account for trading fees

6. "ExchangeNotAvailable"

• Solution: Check exchange status/maintenance
• Retry after a delay
• Use different exchange endpoint if available

7. WebSocket connection drops

• Solution: Implement reconnection logic
• Use try-catch and restart

  watch*

  methods
• Check network stability

Debugging

// Enable verbose logging
exchange.verbose = true

// Check exchange capabilities
console.log(exchange.has)
// {
//   fetchTicker: true,
//   fetchOrderBook: true,
//   createOrder: true,
//   ...
// }

// Check market information
console.log(exchange.markets['BTC/USDT'])

// Check last request/response
console.log(exchange.last_http_response)
console.log(exchange.last_json_response)

Learn More

• CCXT Manual
• CCXT Pro Documentation
• Supported Exchanges
• GitHub Repository