Risk management and position sizing

Fix the loss, then derive the size

Amateur sizing works forwards: pick a lot size that feels right, place the trade, discover the loss afterwards. Professional sizing works backwards: decide the loss, place the stop where the chart says it belongs, and let those two numbers determine the lot size. The size becomes an output, never an input.

This inversion has a side effect worth naming. When the loss is fixed, a wider stop no longer means a bigger loss — it means a smaller position. That removes the incentive to cram stops in too tight, which is the most expensive habit in retail trading, because a stop placed for comfort rather than for structure gets hit by ordinary noise.

Why 1% to 2%, and not more

The standard advice is to risk one or two percent of the account per trade. It is not superstition; it is what a losing streak does to compounding. Losses shrink the base that future gains work on, so the damage is not linear.

• Ten consecutive losses at 1% per trade leaves roughly 90% of the account. A 11% gain gets it back.
• At 2%, the same streak leaves about 82%. Recovering needs 22%.
• At 5%, it leaves 60%, needing a 67% gain.
• At 10%, it leaves 35%, and you need to nearly triple what is left to break even.

Ten losses in a row is not exotic. A strategy that wins 50% of the time produces a ten-loss streak roughly once every thousand trades, which is a couple of years of active trading. The percentages above decide whether that event is an inconvenience or the end of the account.

Leverage and margin are a separate question

Leverage is routinely blamed for blown accounts, and it is the wrong culprit. Leverage determines how much collateral your broker locks up to hold a position — at 1:100, a 10 000 USD notional position ties up 100 USD of margin. It does not change what the position gains or loses per pip.

What actually blows accounts is position size. A trader with 1:500 leverage who risks 1% per trade is far safer than one with 1:30 who risks 20%. Higher leverage is dangerous only because it removes the natural ceiling that would have stopped an oversized trade from opening at all. Size the trade by risk and leverage becomes a footnote — relevant for whether the trade fits, not for what it costs.

Where correlation quietly doubles your risk

Sizing each trade at 1% is only meaningful if the trades are independent. Long EURUSD, long GBPUSD and short USDCHF at 1% each is not three separate 1% risks; it is one 3% bet against the dollar, and all three will lose together on a dollar rally.

The practical fix is to think of risk per theme rather than per trade. Decide what a dollar-direction bet is allowed to cost you in total, then split that budget across however many positions express it. The same applies to gold and silver, to the American indices, and to bitcoin against most of the altcoin complex.

Frequently asked questions