portfolios.tools

Investing

Compound interest, CAGR, dollar-cost averaging, total return, real return, and lump sum vs periodic comparisons for evaluating investment performance over any time horizon.

Stock Chart

Real-time stock prices with interactive candlestick charts and SMA overlays.

Compound Interest Comparator

Compare multiple investment scenarios side by side: monthly vs annual, tax-deferred vs taxable.

Margin Interest Calculator

Compute daily/monthly/annual margin interest cost for any brokerage rate.

Lump Sum vs Periodic

Compare upfront lump sum against dollar-cost averaging over time.

Sharpe & Sortino Ratio

Compute Sharpe and Sortino ratios to measure risk-adjusted returns.

DCA Price Averager

Compute real average cost per share from periodic buys: compare DCA vs lump sum.

Real Return (Inflation-Adjusted)

Adjust nominal returns for inflation with the Fisher equation: see real purchasing power.

Total Return

Price change + dividends + splits with CAGR breakdown and annualized return.

Time Weighted Return

Geometric linking of sub-period returns vs simple return with cumulative table.

Money Weighted Return

Compute IRR or XIRR from irregular cash flows with dates: measure your personal rate of return accounting for deposit...

CAGR Finder

Compound annual growth rate between two values over any period.

CAGR Reverser

Years needed to reach a target at a given CAGR with projection table.

Stock Split Adjuster

Adjust share count and cost basis after forward or reverse splits.

Position Sizing

Risk based share count from entry, stop loss, and portfolio risk percent.

Risk to Reward Ratio

Evaluate trades with RRR, Kelly criterion, and break even win rate.

Stock Average Down

Calculate New Breakeven Cost Basis When Buying Additional Shares.

Trailing Stop Loss

Generate Progressive Stop Loss Levels to Lock in Profits.

Unix Market Timezone

Convert Unix timestamps to global exchange session times.

Base64 Payload Tool

Encode, decode, and pretty print Base64 in the browser.

Cron Market Scheduler

Generate cron expressions aligned to market hours.

JWT Debugger

Decode JWT header and payload safely client side.

ETF Expense Ratio Simulator

Compare low vs high MER compounding drag over decades.

Inflation Erosion Calculator

See purchasing power decay of cash over time with year by year table.

Subscription Fatigue Audit

Aggregate recurring fees and 10 year investment opportunity cost.

Lifestyle Inflation Tracker

Track how much of each raise you save vs spend over your career.

Sinking Fund Planner

Smooth monthly savings targets for irregular annual expenses.

Lease vs Buy Calculator

10 year car lease vs buy cost with invested difference opportunity cost.

Broker Fee Break Even Matrix

Flat fee vs percentage broker costs and break even deposit size.

FX Spread Cost Calculator

Reveal hidden currency conversion fees in broker FX spreads.

Lost Decade Backtester

Simulate portfolio behavior during flat market periods with bundled historical data.

DCA Vs Lump Sum

Compare lump sum vs dollar cost averaging historically.

Cash Drag Estimator

Quantify opportunity cost of holding cash vs invested.

Kelly Criterion Position Sizer

Optimal bet size from win probability and payoff odds.

Tracking Error Calculator

Free tracking error and information ratio calculator. Measure active risk by comparing portfolio returns against a benchmark index over time.

Rolling Returns Visualizer

Free rolling returns calculator. Compute 3 year, 5 year, and 10 year rolling performance windows from any annual return series.

RSI Calculator

Calculate Wilder RSI from a closing price series, identify overbought and oversold zones, and inspect recent momentum readings privately in your browser.

ATR Calculator

Calculate Wilder Average True Range, normalize volatility against price, and estimate a risk based position size from high, low, and close data.