Position Size Calculator
Calculate the exact lot size for any trade based on your account balance, risk tolerance, and stop loss. Never over-risk again.
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📉 Loss Streak Simulator
See how your account holds up after consecutive losses at your current risk level:
Understanding Position Sizing
Why Position Sizing Matters
Position sizing is arguably the most important aspect of risk management. Even with a winning strategy, poor position sizing can blow your account. Conversely, proper sizing lets you survive inevitable losing streaks and stay in the game long enough for your edge to play out.
The 2% Rule
Most professionals risk no more than 1-2% of their account per trade. At 2% risk, you could lose 10 trades in a row and still retain over 80% of your capital. At 10% risk per trade, just 7 consecutive losses would wipe out half your account.
How Stop Loss Affects Size
A wider stop loss means a smaller position size (and vice versa). This is by design — whether your stop is 20 pips or 200 pips away, your dollar risk stays the same. The position size adjusts automatically to keep your risk constant.
Common Mistakes
The biggest mistake is using the same lot size for every trade regardless of stop distance. Traders also often increase position size after a win (overconfidence) or after a loss (revenge trading). Consistent position sizing removes emotion from the equation.
Frequently Asked Questions
What is position sizing in forex trading?
Position sizing determines how many lots or units to trade based on your account size, risk tolerance, and stop loss distance. It ensures you never risk more than a set percentage of your account on any single trade, protecting you from catastrophic losses.
How much should I risk per trade?
Most professional traders risk between 1-2% of their account balance per trade. Beginners should start at 0.5-1% while they develop consistency. The lower the risk per trade, the longer you can survive inevitable losing streaks.
Does a wider stop loss mean more risk?
No — that's a common misconception. A wider stop loss simply means you trade a smaller position size. Your actual monetary risk stays the same. Whether your stop is 20 pips or 200 pips, this calculator ensures you risk the same percentage of your account.
What if the calculator gives me a fractional lot size?
Always round DOWN to the nearest lot size your broker supports. If the calculator says 0.37 lots and your broker's minimum increment is 0.01, use 0.37. If your broker only supports 0.1 increments, use 0.30. Never round up — rounding up means risking more than planned.