Stock Position Size Calculator
Knowing exactly how many shares to buy on every trade is one of the most critical skills in trading. A stock position size calculator removes the guesswork by computing the optimal number of shares based on your account size, the percentage of capital you are willing to risk, and the distance between your entry price and stop loss.
Why Position Sizing Matters for Stock Traders
Professional traders never risk more than a small percentage of their account on a single trade, typically between 0.5% and 2%. This discipline ensures that even a string of losing trades will not blow up a trading account. Without proper position sizing, you are gambling rather than trading. A position size calculator enforces consistent risk management on every single trade, whether you are day trading volatile small caps or swing trading large cap stocks.
The Position Size Formula
The formula for calculating position size is straightforward:
For example, if you have a $50,000 account and you are willing to risk 1% per trade ($500), and your entry price is $150 with a stop loss at $145, the dollar risk per share is $5. Dividing $500 by $5 gives you 100 shares. This is the maximum number of shares you should buy to stay within your risk parameters.
Features of the EZtrade Stock Calculator
EZtrade goes beyond a simple calculator. It offers live price feeds so your entry price auto-fills, multi-target R:R analysis with up to 5 take-profit levels, a built-in trade journal to log the results, and cloud sync so your data is available on every device. Prop firm traders can also set daily loss limits to stay within funded account drawdown rules. The calculator supports both long and short positions, and works with any US-listed stock or ETF.
Try the Calculator Now
No sign-up required. Calculate your position size in seconds.
Frequently Asked Questions
What is position sizing?
Position sizing is the process of determining how many shares or contracts to trade based on your risk tolerance. It is the foundation of risk management and ensures no single trade can cause catastrophic losses to your trading account.
How much should I risk per trade?
Most professional traders risk between 0.5% and 2% of their account per trade. Beginners should start at the lower end (0.5% to 1%) until they have a proven strategy with a positive expectancy.
Does EZtrade work for day trading and swing trading?
Yes. EZtrade works for any trading style. Whether you are scalping with tight stop losses or holding swing trades for days, the position size calculator adjusts to your specific risk parameters.
Related tools: Futures Position Size Calculator | Risk Reward Calculator | Trading Journal