Understanding Position Sizing: More Than Just 'How Much'

There's a lot of talk about finding good trades, but often less emphasis on the how much you put on a trade, which is just as, if not more, critical to long-term survival. Position sizing isn't just about throwing a certain percentage of your account at an idea; it's a dynamic calculation that should incorporate your risk tolerance, your stop-loss placement, and the actual volatility of the asset you're trading.

Let's say you're looking at a stock like $MRVL. If your typical stop loss is 1% of your account value, and you've identified a good entry with a stop at, say, 208, from a current price of 216, that's an 8-point risk. If $MRVL had a much tighter range, perhaps more like $Y's movement today (847.62-847.9), your stop would naturally be much closer, meaning you could take a larger share size for the same dollar risk. The key takeaway is to define your dollar risk per trade first, and then work backward to determine your share size based on your stop-loss placement. It's about protecting capital above all else.