Trading Percentage Calculator - ROI & Performance Analysis

Use the formula: ((New Price - Old Price) / Old Price) × 100. This gives you the percentage change, positive for gains and negative for losses. Multiply by your position size to get profit/loss.

Percentage change measures price movement of an asset, while ROI measures the return on your investment including any costs, fees, and the actual amount invested. ROI is more comprehensive for trading analysis.

To annualize returns, use: ((Current Value / Initial Investment)^(12/months) - 1) × 100. This accounts for compounding and gives you a standardized annual comparison across different time periods.

For single trades, use simple percentage change. For portfolio tracking over time, compound returns are more accurate as they account for reinvestment of gains and provide a clearer performance picture.

The Kelly Criterion determines optimal position sizing based on win rate and average win/loss ratio. Formula: f = (bp - q) / b, where b = odds received, p = probability of winning, q = probability of losing.

Sharpe ratio = (Portfolio Return - Risk-free Rate) / Portfolio Standard Deviation. A ratio above 1.0 is good, above 2.0 is excellent. It measures risk-adjusted returns - higher is better.

A profit factor above 1.5 is considered good, above 2.0 is excellent. It's calculated as Gross Profit / Gross Loss, measuring the profitability of your trading strategy over time.

Trading costs (spreads, commissions, slippage) reduce net returns. Our calculator shows both gross and net P&L to help you understand the true cost of trading and optimize your strategy.