Learn -- lesson 9 of 10
Position sizing basics: why size decides survival
What you'll learn: why how much you put into a position often matters more than whether you were right about direction.
Position sizing is simply the decision of how much of your capital to put into a single position. It sounds like the least interesting part of investing, but it's arguably the part that decides whether you're still in the game after a bad stretch. Two people can share the exact same view on Bitcoin's direction and end up with completely different outcomes purely because they sized their positions differently.
The core idea is straightforward: a position sized too large relative to your total capital turns an ordinary, survivable drawdown into a forced, painful decision -- selling at the worst possible time because the position has become too large to comfortably hold, not because the original view was wrong. A position sized appropriately can absorb the same drawdown and simply wait it out.
This page is a general, educational explanation of a concept. General market information and research, not personalized investment advice -- it does not tell you what size is right for you, because that depends on your own circumstances, time horizon and risk tolerance, which nobody on the internet can know on your behalf.
How to read it
- Being right about direction and surviving the ride to be right are two different problems -- position sizing is entirely about the second one.
- The same drawdown percentage is comfortable at a small size and unbearable at a large size -- the price move doesn't change, your ability to sit through it does.
- Sizing decisions are easier to make calmly before a position exists than while it is already down and moving fast.
- A position that forces you to make decisions out of panic was, in hindsight, probably sized too large from the start.
Common beginner mistakes
- Sizing a position based on how confident you feel right now, rather than on how large a realistic drawdown could be and whether you could sit through it.
- Increasing size after a string of wins because it 'feels like it's working' -- confidence and correct sizing are not the same thing.
- Treating position sizing as a one-time decision rather than something to revisit as conditions (like volatility) change.