How to Get Candlestick and Bar Prices in MQL4

You’re staring at a chart, and you know the story is in the bars—the opens, the highs, the lows, the closes. Whether you're coding an Expert Advisor to spot a breakout or just trying to understand why that last trade went south, you need a way to pull those numbers into your MQL4 code. It’s the foundation of almost any automated strategy, yet it’s surprisingly easy to get tripped up by the way MetaTrader actually stores this data.

In MQL4, every bar’s price data is sitting there, waiting for you to grab it. The key is understanding how it’s organized.

First, forget everything you know about reading a chart from left to right. MetaTrader stores price data in something called a timeseries array. In a timeseries, the very first element, index 0, is always the current bar. Index 1 is the bar before that, 2 is the one before that, and so on . So, when you're looking at a 1-hour chart and you want the close price of the last complete hour, you’re asking for Close[1].

The Two Main Ways to Get Your Prices

There are two clear paths to getting this data, and each has its place.

Method 1: The Predefined Arrays (The Quick Route)

If you're working on the current chart, this is the easiest and fastest method. MQL4 gives you four built-in arrays that are automatically filled with the price data for the current symbol and timeframe .

• Open[] – The opening price.
• High[] – The highest price.
• Low[] – The lowest price.
• Close[] – The closing price.

Here’s how you’d use them in a script or EA:

// Get the current bar's open price
double currentOpen = Open[0];

// Get the closing price of the previous bar
double previousClose = Close[1];

// Find the highest price of the bar 3 bars ago
double highThreeBarsAgo = High[3];

While this is super convenient, remember that Close[0] is the current price, which is still changing. For a final, confirmed close, you'll want Close[1] .

Method 2: The i Functions (The Versatile Route)

Need data from a different symbol or timeframe than the one you're looking at? That’s where the i functions shine. Functions like iOpen(), iHigh(), iLow(), and iClose() let you specify exactly what you want .

The format is simple: iOpen(symbol, timeframe, shift).

// Get the current close price for EURUSD on the H1 chart
double eurUsdH1Close = iClose("EURUSD", PERIOD_H1, 0);

// Get the open price of the previous bar on the current chart
double currentSymbolOpen = iOpen(Symbol(), 0, 1);

This flexibility is essential for strategies that watch multiple pairs or timeframes simultaneously. You can also use functions like iHigh() and iLow() to find the highest or lowest value over a specific number of bars , giving you a quick way to build a range check.

Beyond the Code: A Faster Way to Watch?

Once you’ve written your code, you’ll find yourself jumping back and forth—running a test, checking the chart, tweaking a number. That’s the cycle. But when you’re actually managing the positions that your logic is built to trade, the constant need to bring MetaTrader’s full window to the front just to check a current quote can break your flow.

That’s where Camovia Tray comes in. It essentially turns your MT5 or MT4 into a tray tool, giving you a quick, local snapshot of live quotes by simply hovering over the system tray icon. You can manage open positions—seeing their current profit and loss—and even close them with a click, all without restoring the full platform. It’s a quick way to stay on top of the market data, especially when you're refining your code and want to see the direct impact of the bars and prices you're working with.