GugoPro Academy
← Back to courses & tools
Risk control · 17

Position sizing and risk budgeting

A good idea paired with an oversized position can still cause irreversible losses. Position size should start from "how much will I lose if I'm wrong", not from "how much money do I have".

1. First define failure conditions

Stop‑loss is not just a price percentage; it is an observable condition signalling investment‑thesis failure, e.g., loss of competitive advantage, cash‑flow deterioration, or change in capital allocation. If you cannot describe failure conditions, do not size the position.

2. The formula for risk budgeting

Maximum shares = affordable loss ÷（entry price − stop price + cost per share）

Loss tolerance can be approximated as account equity multiplied by per‑trade risk percentage. The formula is an upper bound and remains subject to liquidity, gaps, concentration and investment policy limits.

3. Avoid the precision illusion

Markets can gap past stop‑loss prices and trading costs widen under stress; therefore keep a safety buffer and aggregate exposure across the same industry, same factor and correlated assets.

OpenPosition Size Calculator，then useHistorical VaR toolCheck the overall portfolio, not just a single trade.

Financial risk disclaimer

This page, its calculators, and examples are for education, research, and scenario estimation only. They are not personalized investment, trading, betting, tax, legal, or financial advice. Markets and local rules can change quickly; verify current primary information and take responsibility for your decisions. Past performance, model outputs, and simulations do not guarantee future results.