Sizewise

Know exactly how much to buy before you trade. Never risk more than you decided.

💡 Why position sizing matters

Bad traders decide how many shares to buy first. Good traders decide how much they're willing to lose first.

The Casino Analogy

You have $1,000 for the night. Do you bet it all on one hand? Or $20 per hand so a losing streak doesn't wipe you out? Position sizing is the $20 strategy — it keeps you in the game.

How it works
Account × Risk % ÷ Risk per share = Shares to buy
Use this tool when:
  • You have a trade idea and know your entry price
  • You've set a stop-loss (where you'll cut losses)
  • Before you click "buy" — every single time
1 Your account
Risking 2% means: "If this trade hits my stop, I lose 2% of this amount"
2 Trade setup
The gap between Stock Price and Stop-loss = your risk per share
Used to calculate Reward:Risk ratio. A 2:1 ratio means you can profit $2 for every $1 risked.
Advanced settings
Comma-separated values (default: 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4)
Risk per share —
💰 Account $100,000
→
⚡ Risk 2% $2,000 max loss
→
📉 Risk per share $10
→
📦 Buy 200 shares

Enter your trade details above to see your position size

What "Risk %" means: This is how much of your account you LOSE if the trade hits your stop-loss. It is NOT how much of your account you invest.

Risk % Shares Trade value Actual risk % of account R:R
Recommended 2% is the sweet spot: you can survive 50 losing trades in a row before halving your account.