Last Updated on 11 September, 2023 by Samuelsson

Position sizing is the process of determining the number of shares or contracts to buy or sell in a particular trade. It is an essential aspect of risk management, as it helps traders determine the potential return and risk of a trade before entering it. In this ebook, we will cover the basics of position sizing, including how to calculate position size and how to use different position sizing strategies to manage risk.

Calculating Position Size

The first step in position sizing is to determine the amount of capital that you are willing to risk on a trade. This is known as your “risk capital” or “trading capital.” It’s important to remember that you should never risk more capital than you can afford to lose.

Once you have determined your risk capital, you can calculate your position size using the following formula:

Position Size = Risk Capital / (Stop Loss * Price)

Where:

• “Risk Capital” is the amount of capital that you are willing to risk on a trade.
• “Stop Loss” is the distance between your entry price and your stop loss order.
• “Price” is the entry price of the trade.

For example, let’s say that you have $10,000 in risk capital and you are willing to risk 1% of that capital on a trade. You are entering a long trade on a stock at $50 with a stop loss of $48. Your position size would be:

Position Size = $10,000 * 0.01 / ($50 – $48) = 2,000 shares

This means you would purchase 2,000 shares of the stock.

Position Sizing Strategies

There are many different position sizing strategies that traders can use to manage risk. Some of the most common include:

Fixed Ratio Method

The fixed ratio method is a simple strategy that involves using a fixed ratio of position size to account size. For example, a trader may use a 1:3 ratio, meaning that for every $3 in their account, they will trade $1. This method helps to ensure that a trader does not over-leverage their account and can survive a string of losses.

Fixed Dollar Method

The fixed dollar method involves risking a fixed dollar amount on each trade, regardless of the trade’s potential return or the trader’s account size. For example, a trader may risk $500 on each trade. This method can be useful for traders who are less confident in their ability to accurately predict potential returns.

Kelly Criterion

The Kelly Criterion is a more advanced strategy that involves using a mathematical formula to determine the optimal position size based on the probability of a winning trade and the potential return. It is a widely used method to optimize the risk reward ratio.

Related reading: The Best Position Sizing Method

Conclusion

Position sizing is an essential aspect of risk management in trading. By determining the appropriate position size before entering a trade, traders can better manage their risk and increase their chances of success. There are many different position sizing strategies that traders can use, including the fixed ratio method, fixed dollar method, and Kelly Criterion. By understanding and implementing these strategies, traders can improve their risk management skills and increase their chances of long-term success.