This free Excel position sizing calculator helps traders determine exactly how many shares to buy on every trade. It supports three methods — fixed fractional, Kelly criterion, and volatility-based (ATR) sizing — so you can compare outputs and choose the approach that fits your strategy. Download it, plug in your account size and risk parameters, and get precise share counts in seconds.
What’s Included
- Fixed Fractional Worksheet — Enter your account size and risk percentage to calculate position size for any trade with a defined stop-loss
- Kelly Criterion Calculator — Input your historical win rate and average win/loss ratio to find the mathematically optimal bet size, with adjustable Kelly fractions (full, half, quarter)
- Volatility-Based (ATR) Sizing — Uses Average True Range to set stop distances dynamically, sizing positions based on recent price volatility rather than fixed dollar stops
- Account Risk Summary — A dashboard row showing your total open risk across all current positions, helping you avoid portfolio-level overexposure
- Trade Size Comparison Table — See the output of all three methods side by side for the same trade setup, making it easy to pick the most appropriate size
- Max Position Safeguards — Conditional formatting flags any position that exceeds your maximum size limit or would push total portfolio risk beyond your threshold
- Pre-Built Formulas — Every calculation is formula-driven with no macros required, so you can audit the math and customize as needed
How to Use
Step 1: Enter Your Account Details
Open the Account Setup sheet and enter your total account equity in cell B2. Set your default risk per trade as a percentage in B3 (e.g., 1.5 for 1.5%). Enter your maximum single-position limit in B4 — this acts as a hard cap regardless of what the formulas suggest.
Step 2: Set Your Trade Parameters
On any of the three method tabs, enter the stock ticker in column A, your planned entry price in column B, and your stop-loss price in column C. The spreadsheet calculates the per-share risk (stop distance) in column D automatically.
Step 3: Choose a Sizing Method
The Fixed Fractional tab uses your account size and risk percentage to output share count directly. The Kelly tab requires your win rate and average win/loss ratio — enter these in the header cells, and the recommended size appears per trade. The ATR tab pulls a manually entered ATR value to set the stop distance instead of a fixed stop price.
Step 4: Review Position Limits
Column F on each tab shows a status flag. Green means the position is within your limits. Red means the calculated size exceeds either your max position cap or would push total portfolio risk above your threshold. Never override a red flag without deliberately adjusting your risk parameters first.
Step 5: Log and Track
Once you have your position size, transfer it to your trade planning worksheet or trading journal before executing. This creates a pre-trade record you can review later to evaluate whether your sizing rules held up over time.
Key Benefits
- Eliminates guesswork — Stop eyeballing share counts or rounding to convenient numbers. Every position is calculated from your actual risk parameters.
- Three methods, one file — Compare fixed fractional, Kelly, and ATR-based sizing for the same trade to understand how each method behaves differently.
- Built-in risk guardrails — The safeguard formulas catch oversized positions before you place the trade, not after.
- Scales with your account — All formulas are percentage-based, so the spreadsheet works whether your account is $5,000 or $500,000.
Template vs JournalPlus App
| Feature | This Template | JournalPlus App |
|---|---|---|
| Position Sizing Methods | 3 methods (manual input) | Auto-calculated from trade data |
| Risk Per Trade | Manual percentage entry | Auto-tracked with real P&L |
| Portfolio Exposure | Basic summary formulas | Real-time across all accounts |
| Trade Logging | Copy-paste to journal | Auto-imported from 50+ brokers |
| Historical Analysis | Manual chart building | 30+ built-in performance metrics |
| Customization | Fully editable spreadsheet | Configurable dashboards |
| Price | Free | $159 one-time |
This spreadsheet is a solid tool for traders who want full control over their sizing calculations. When you’re ready for automatic trade imports and want your position sizing data connected to your actual performance metrics, JournalPlus picks up where the spreadsheet leaves off.
Download
Download the free position sizing calculator spreadsheet and start sizing every trade to your exact risk parameters. No account required — just open it in Excel or Google Sheets and start using it immediately.
Frequently Asked Questions
What is the best position sizing method for beginners?
Fixed fractional sizing is the simplest starting point. Risk a fixed percentage of your account (typically 1-2%) per trade. This method scales naturally — your position sizes grow as your account grows and shrink during drawdowns. Once you have enough trade history, you can experiment with Kelly criterion using your risk management spreadsheet data.
How do I calculate position size from a stop-loss?
Divide your dollar risk (account size × risk percentage) by the per-share risk (entry price minus stop-loss price). For example, a $50,000 account risking 1% with a $2 stop distance gives you $500 ÷ $2 = 250 shares. This Excel position sizing calculator spreadsheet automates this math across all three methods.
Is the Kelly criterion safe for trading?
Full Kelly sizing is aggressive and can lead to large drawdowns. Most traders use half-Kelly or quarter-Kelly to reduce volatility while still capturing the mathematical edge. This spreadsheet lets you adjust the Kelly fraction in cell E2 on the Kelly tab to find a level that matches your risk tolerance.
Can I use this position sizing calculator for options trading?
This calculator is designed for stock and ETF positions where you set a stop-loss price. For options, position sizing is typically based on the premium paid rather than stop distance. The fixed fractional method still works — just use the total premium as your dollar risk. For dedicated options tracking, check the options trading journal template.
How often should I update my position sizing inputs?
Update your account size at the start of each trading week or after any significant drawdown. Risk percentage and max position limits should be reviewed monthly or whenever your strategy changes. Keeping a day trading journal alongside this calculator makes it easier to spot when your sizing rules need adjustment.
