Position Size Calculator
Calculate optimal position size based on your account balance and risk tolerance.
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Understanding Position Sizing
What is Position Sizing?
Position sizing determines how many shares or contracts to buy/sell in a single trade. It is one of the most critical aspects of risk management. Proper position sizing ensures you survive losing streaks while giving winning trades room to grow.
Position Size Formula
Calculation: Shares = Risk Amount ÷ |Entry - Stop| = (Account × Risk %) ÷ |Entry - Stop|
Risk Management Rules
💰 The 1% Rule
Never risk more than 1% of your account on a single trade. With $10,000, max risk is $100.
📊 The 2% Rule
Maximum 2% per trade for experienced traders who have backtested the strategy.
Example: Account: $10,000 | Risk: 1% ($100) | Entry: $50 | Stop: $47 | Position = $100 ÷ $3 = 33 shares. If stopped out, you lose $99.
Frequently Asked Questions
Why is position sizing important?
Position sizing is the #1 risk management tool. Without it, a few bad trades can wipe out your account. The 1-2% rule ensures you survive losing streaks.
What is the 2% rule?
Never risk more than 1-2% of your total account on a single trade. With $10,000, that's $100-$200 max risk per trade. This protects you from catastrophic losses.
What is this tool?
A position size calculator determines the optimal number of shares or contracts to trade based on your account size, risk per trade, and stop-loss distance. It prevents overexposure by ensuring you never risk more than a predetermined percentage of your capital on any single trade. Key to long-term trading survival and consistent risk management.
How to use
- 1
Enter account size
Input your total trading account balance.
- 2
Set risk percentage
Enter the percentage of account you risk per trade (typically 1-2%).
- 3
Set stop-loss
Enter your entry price and stop-loss price.
- 4
View position size
See optimal position size in shares/contracts and dollar risk amount.
Frequently Asked Questions
What percentage should I risk per trade?
Professional traders typically risk 1-2% of their account per trade. Conservative traders risk 0.5-1%. Never risk more than 3-5%. The lower your risk per trade, the more consecutive losses you can survive without devastating your account.
Why is position sizing more important than entry/exit?
Even the best entry strategy will fail if your position sizes are wrong. Proper position sizing ensures you survive drawdowns, manage emotions, and maintain consistent risk. Warren Buffett's success is largely due to position sizing—putting more capital on high-conviction bets.
What is the 2% rule in trading?
The 2% rule states that you should never risk more than 2% of your total account on any single trade. If you have a $50,000 account, your maximum loss per trade should be $1,000. This ensures you can survive a streak of consecutive losses. After 10 losses in a row at 2% risk, you'd still have about 82% of your account. This is the cornerstone of professional risk management.