Leverage is the amount of market exposure controlled relative to the capital supporting it. Margin is the collateral or equity required to open or maintain that exposure. They are related, but they answer different questions.
Leverage tells you how strongly market movement can affect account equity. Margin tells you how much capital a broker, exchange or clearing arrangement requires for the position. Neither one tells you how much risk is appropriate for your objective.
Measure leverage as exposure relative to capital
A simple gross leverage measure for a linear position is:
Leverage = market exposure ÷ account equity.
If 20,000 units of equity support 100,000 units of market exposure, the position represents 5× exposure relative to equity. A 1% adverse move in a simple linear 100,000-unit position is about 1,000 units before costs, which is 5% of 20,000 equity.
This example is deliberately simplified. Derivatives can have nonlinear sensitivities, contract multipliers and changing exposures, so the correct risk measure depends on the instrument.
Margin is not the amount you can lose
One of the most dangerous misunderstandings is treating the margin deposit as a maximum loss. Margin is a financing or collateral requirement. The market loss is driven by the position's exposure and price movement.
Depending on the product and legal structure, losses can consume a large part of the account, trigger additional collateral requirements, or exceed the amount initially posted. The exact rules are market- and provider-specific.
Available buying power is not risk capacity
A platform may show that the account has enough buying power to open a large position. That is a permissions calculation, not a risk recommendation.
The account can be technically allowed to open exposure that would create an unacceptable drawdown after an ordinary adverse move. MFXG therefore starts with the risk budget and position size, then checks whether the resulting position also satisfies margin requirements.
Margin requirements can change
Margin rules vary across securities, futures, foreign exchange, CFDs, options and other leveraged products. Firms and clearing arrangements can also change requirements as market conditions or product risk changes.
In securities margin accounts, for example, regulators and brokerage firms impose initial and maintenance requirements, and firms may use stricter house requirements. If account equity falls below the applicable requirement, the firm may require more collateral or liquidate positions. Other markets use different mechanisms.
The risk-management lesson is broader than any one rule: a leveraged position can be forced to change because of margin conditions even when the trader would otherwise prefer to keep it open.
Leverage magnifies both gains and losses
Leverage does not change the direction of the market move; it changes the effect of that move on the capital base. With more exposure supported by the same equity, favorable moves produce larger account gains and adverse moves produce larger account losses.
That amplification is why high leverage can turn a normal fluctuation into a material equity event.
Position sizing should come before leverage optimization
The correct sequence is not “How much leverage can I get?” It is “How much can I lose, where is the trade invalidated, and what position size fits that loss?”
The Position Sizing page owns that calculation. Leverage is then checked as a consequence of the resulting exposure. If the position requires excessive leverage or leaves too little margin cushion, the size should be reconsidered.
Margin calls create path-dependent risk
A leveraged trade can be forced out before the market reaches the trader's long-term thesis if equity falls enough to violate a margin requirement. This creates path dependence: the eventual market direction is irrelevant if the account cannot survive the interim movement.
Forced liquidation can also occur during unfavorable liquidity, making realized outcomes worse than a model that assumes voluntary exits at normal spreads.
Portfolio leverage is more than one position
Several individually modest leveraged positions can create large total exposure. Gross exposure measures how much market value is controlled in total, while net exposure can show directional offset between long and short positions.
Those measures are useful but incomplete because long and short positions may not offset when correlations change. The portfolio exposure and correlation risk pages handle that broader account view.
Leverage can interact with volatility
If volatility rises while leverage stays unchanged, the distribution of account-level gains and losses can widen. A position that was manageable in a quiet regime can become too aggressive when normal price movement expands.
This is one reason volatility-adjusted sizing can be useful as a risk-control method. The method does not make volatility predictable; it changes exposure when the estimated size of price movement changes.
Common leverage and margin mistakes
- treating available buying power as safe position size;
- assuming the margin deposit is the maximum possible loss;
- ignoring the possibility that margin requirements change;
- using leverage without a defined account-level loss budget;
- looking at one position while ignoring total portfolio exposure;
- assuming offsetting positions will remain offsetting under stress.
A practical leverage check
Before opening a leveraged position, calculate the notional or effective exposure, the account equity supporting it, the expected loss at invalidation, the margin requirement, the remaining margin cushion and the loss under a worse-than-planned price move.
Then repeat the calculation at portfolio level. If the account only works under the assumption that volatility, correlation and margin rules remain comfortable, the leverage is fragile.
Leverage and margin inside the MFXG framework
The parent Risk Management pillar treats leverage as an amplifier, not an edge. It can improve capital efficiency, but it cannot make a weak trade better or a poor risk budget safer.
The later Forex cluster has a separate page for foreign-exchange-specific leverage and margin conventions. This page owns the general risk concept across markets.