Position sizing

How much capital to allocate per trade based on maximum acceptable risk.

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Who this is for — Anyone who enters with good ideas but inconsistent size: too large when impulsive, too small when afraid. Position sizing makes risk repeatable.

Position sizing turns a risk rule into operational quantity: first you decide how much you can lose, then you calculate size. It does not start from conviction; it starts from the limit.

In plain terms — First choose maximum tolerable damage, then choose how many units to buy or sell. If you reverse the order, the market decides for you.

Bronze prerequisite — Before this lesson: stop-loss, trade-size, take-profit, risk-per-trade. See bronze-path.


Practical formula and checks

Base formula: monetary risk per trade / distance between entry and stop = size.

Before sending the order, always verify three points:

  1. Theoretical loss respects your risk-per-trade.
  2. Stop is technical, not "psychological" (technical-stop).
  3. Size does not exceed allocated-capital planned for that market.

When volatility rises, stop distance increases and size must fall. That is correct behaviour, not a problem to work around.

Example — Capital €20,000, risk per trade 0.5% = €100. Entry at 50, stop at 48, distance €2. Maximum size: 50 units. If you widen the stop to €2.5, correct size drops to 40 units.


Typical sizing mistakes

  • Increasing size after two winners to "push" the account.
  • Keeping fixed size even when volatility changes.
  • Calculating risk while ignoring costs and slippage.
  • Tightening the stop only to fit a larger size.

Card

  • What it is: rule that converts maximum risk into operational quantity.
  • Why it matters: protects capital and avoids emotional leverage errors.
  • Quick check: risk first, then size, then the order.

Silver path — Module: Position management. Part of silver-path.