FREE EXPLAINER · BEGINNER FOUNDATION
What Is Position Sizing?
Position sizing is deciding how much money to allocate to one trade or investment.
The simple explanation
Position sizing is deciding how much money to allocate to one trade or investment.
Why it matters
A sensible idea can still cause serious damage if the position is too large.
A simple way to think about it
Work backwards from acceptable loss, entry, invalidation point and portfolio exposure. Size should fall when uncertainty or volatility rises.
A common beginner mistake
Choosing size based on excitement or confidence alone.
What to check next
- Check that you understand the definition in plain English.
- Look at the company, market and timeframe rather than one number alone.
- Ask what could change the interpretation.
- Keep risk separate from excitement or certainty.
One calm takeaway
Position sizing is deciding how much money to allocate to one trade or investment. Use it as one piece of context, never as a promise about what happens next.