Ask a professional trader what they're most disciplined about and the answer is rarely entries — it's sizing. Position size is the one variable that decides whether a losing streak is a drawdown or an ending, and it's fully under your control. The industry-standard framework takes five minutes to learn.
The fixed-fractional model
Risk a fixed percentage of your account on every trade, and let the stop distance determine the size:
Position size = (account × risk %) ÷ stop distance %
Worked example: $20,000 account, 1% risk ($200), long entry at $140 with a stop at $136.50 (2.5% below). Size = 200 ÷ 0.025 = $8,000 notional (≈57 SOL). If the stop hits, you lose $200 — exactly the 1% you chose, regardless of how dramatic the chart looked. Our position size calculator runs this formula, including margin requirements and leverage caps.
Note what the formula implies: tight stops permit bigger positions; wide stops force smaller ones. The risk stays constant. Traders who size every trade identically ("I always buy $5k") are unknowingly risking wildly different amounts depending on their stop placement.
Why leverage is not risk
Leverage never appears in the sizing formula — deliberately. In the example above, 10x leverage means posting $800 margin for the $8,000 position; 2x means $4,000. The $200 at risk is identical. Risk lives in size × stop distance; leverage only sets the margin deposit. A 20x position with a tight stop can risk less than an unleveraged bag held with no stop at all.
Leverage does add a constraint: liquidation must sit *well beyond* your stop, or the exchange exits you before your plan does — check with the liquidation calculator. And it scales the *relative* weight of fees and funding, which is its own tax.
Choosing the risk fraction
The standard band is 0.5–2% per trade. The reasoning is survival math across losing streaks — which every strategy has:
- Ten straight losses at 1% → −9.6% drawdown. Annoying; recoverable.
- Ten straight at 5% → −40%. Requires +67% to break even.
- Ten straight at 10% → −65%. Statistically likely to end the account before the strategy's edge can express itself.
Volatile assets don't get bigger risk budgets — they get wider stops and therefore smaller sizes through the same formula. That's the model self-adjusting, not a special case. (Assets that can gap to zero, like meme coins, break the stop assumption entirely — size those as if the full position is the risk.)
The compounding discipline
Recalculate the dollar risk as the account changes: 1% of a growing account grows; 1% of a shrinking account shrinks — automatically de-risking drawdowns and pressing advantages. This anti-martingale property is why fixed-fractional survives where "double down to get it back" dies.
Sizing is unglamorous, which is exactly why it works — it's the edge nobody competes with you for. Entries decide whether one trade wins. Sizing decides whether you're still trading next year.