Size comes last, not first
FOMO traders pick a size by feeling — 'this one looks big'. Disciplined traders pick the entry and stop first, then calculate size so the loss at the stop equals a fixed percentage of the account. Many traders use 0.5–1%.
The formula
Position size = (Account balance × Risk %) ÷ (Distance from entry to stop, per unit).
The stop distance must include the full move to your stop price; add expected fees and spread if they are meaningful.
Stock example
Account: €10,000. Risk: 1% = €100. Entry €50.00, stop €48.00, so risk per share is €2.00. Size = €100 ÷ €2.00 = 50 shares. If the stop is hit, you lose about €100 regardless of how 'sure' the trade felt.
Forex example
Account: $5,000. Risk: 1% = $50. EUR/USD stop is 25 pips away. For a standard lot, one pip is worth about $10, so one mini lot (0.1) is about $1 per pip. $50 ÷ 25 pips = $2 per pip = 0.2 lots. Check your broker's contract specifications, as pip values differ by pair and account currency.
Why it protects you
At 1% risk, ten losses in a row leave you with roughly 90% of your account. At 10% risk, the same streak leaves about 35%. Losing streaks happen to every strategy; sizing decides whether you survive them.
Add a daily stop
Pair per-trade risk with a daily loss limit, for example 3%. Write it as a rule on the Fomo Avoider Alerts page so the AI flags the day you break it.