How MT4, MT5 and cTrader Show Lot Sizes

On MT4, MT5 and cTrader, trade size is always based on lots, even if the ticket sometimes shows units. One lot is defined in each symbol's contract specification and represents a fixed number of units of the base currency or underlying asset. For major forex pairs, by industry convention one standard lot usually equals 100,000 units of the base currency. For CFDs on metals, indices, energies and other markets, the contract size is instrument-specific and must be read from the platform.

Lot size directly affects exposure, margin and the value of each pip or point. The volume field in an order ticket is where a client sets the number of lots or fraction of a lot to trade. A change from 0.10 to 0.20 lots typically doubles both potential profit and potential loss per price increment, assuming the same instrument and account conditions.

Although the underlying definition of a lot is aligned across MT4, MT5 and cTrader via contract size, the display and tools around volume differ. MT4 presents a simple lot input with limited exposure aggregation. MT5 adds extended symbol properties and supports add-on exposure tools. cTrader can show both units and equivalent lots and includes built-in visual risk-based sizing. For Canadian accounts, the same contract sizes apply, while margin and effective exposure per lot may vary with local leverage settings.

On MT4, every new order or modification window includes a Volume field. The number entered in this field is the lot size for that position. Standard market practice is:

• 1.00 - standard lot
• 0.10 - mini lot
• 0.01 - micro lot

The minimum and maximum volume, as well as whether fractional lots are allowed for a symbol, are controlled in the instrument settings on the server side. The client can only submit sizes that fall within these constraints.

To see what 1 lot represents for a particular MT4 symbol:

1. Right-click the symbol in Market Watch
2. Select Specification
3. Check the Contract Size line

Typical examples by convention:

• EURUSD: contract size commonly 100,000 base currency units per lot
• XAUUSD: often 100 troy ounces per lot
• USOIL: often 10 barrels per lot

These figures are defined per symbol and may vary across brokers, so a client should always check the Specification window rather than rely on assumptions. MT4 does not include a native panel that adds up lot sizes across all open trades. Aggregate volume must be calculated manually from the Trade tab or through custom indicators and scripts.

MT5 keeps the same core logic as MT4: an order ticket contains a Volume box that specifies the lot size. The platform accepts fractional lots down to the minimum increment set for the symbol. The limit and step are visible in the symbol properties.

To review the definition of a lot on MT5:

1. Right-click the symbol in Market Watch
2. Choose Specification
3. Locate Contract Size, Volume min, Volume max and Volume step

Typical interpretations:

• Forex pairs: one lot usually equals 100,000 units of the base currency
• Stocks: one lot may equal one share or an exchange-defined lot
• Futures: one lot normally corresponds to one futures contract
• CFD indices, commodities, metals: contract size is specific to the symbol

The Volume min and Volume step parameters determine the smallest permissible trade size and the increment for adjusting position size. This constrains how finely a trader can scale risk in lots. MT5 itself does not ship with a mandatory exposure panel that sums lots across all positions, but an Exposure indicator can be installed from the MetaTrader Market. Once active, it reports total lot size by symbol or overall, giving a consolidated view of current exposure.

cTrader uses the same contract size concept per symbol but presents position size slightly differently. In many layouts, the trade ticket allows input in units, such as 10,000 or 100,000, and shows the equivalent lot size alongside for clarity. Internally, the platform still interprets volume according to each symbol's contract size, which for major FX pairs typically aligns with 100,000 base units per lot.

Contract and volume details are available in the Symbol Info panel. This panel displays:

For CFDs on indices, commodities and metals, the lot often corresponds to one instrument contract or to a quantity defined by the broker settings. Because of this symbol-by-symbol variation, reviewing Symbol Info before trading a new market is standard practice.

cTrader also integrates risk and lot calculation into the chart. The risk-reward trading tool lets a user:

• Set entry, stop-loss and take-profit visually
• Choose a risk level as a percentage of balance or equity
• Have the platform compute the lot size needed to match that risk
• Optionally fix size or target a specific risk-reward ratio

When the order is submitted, the calculated lot size is applied automatically. This reduces manual calculations and makes the relationship between stop distance, risk in account currency and required lot size more transparent.

Across MT4, MT5 and cTrader, the key points are consistent: the lot is the base unit of volume, each symbol has a defined contract size, and the volume value on the ticket determines exposure and pip or point value. Differences lie in how clearly this information is presented and what tools exist around it.

• MT4: straightforward Volume field, contract size shown in Specification, no native total exposure view.
• MT5: same Volume field, more granular symbol settings and optional exposure indicator, with broader multi-asset coverage.
• cTrader: option to work in units with lot equivalence, detailed Symbol Info and integrated visual risk-based sizing.

For Canadian clients, the mechanics of lots match those used globally, while leverage and margin rules may depend on applicable local requirements. A given lot size therefore can imply different effective exposure in a Canadian account than in an offshore account, even when contract size is identical.

Before entering a trade on any platform, checking the contract size and volume parameters for that specific symbol is standard risk practice. This ensures that the chosen lot size aligns with account size, risk tolerance and the applicable margin framework.