Position sizing means deciding how much to buy or sell on a trade based on how much you are willing to lose if it goes wrong. It is one of the most practical ways to keep a single bad trade from causing serious damage to your account.
Start With Risk, Not Reward
Many new traders choose a size because it feels right or because a big win looks tempting. A steadier approach is to decide your maximum loss first.
A common method is to choose a small, fixed percentage of their account to risk on each trade. Then they place a stop-loss at a level where the trade idea is clearly wrong. The distance between entry and stop decides the size.
- Pick the amount of your account you are willing to risk on one trade.
- Measure the distance from your entry to your stop-loss.
- Divide the risk amount by that distance to get your position size.
- Round down if the result does not fit your broker’s lot or share sizes.
Common Sizing Mistakes
Moving a stop further away without reducing size increases risk without you noticing. Adding to a losing position can do the same.
Leverage also deserves care, because it magnifies losses as well as gains. Remember that gaps and fast markets can push a fill past your stop.
Write your sizing rule down and apply it to every trade, including the ones you feel confident about. You can find more risk management guides on SmartTraderBlog.com.
This content is educational and is not financial advice.
