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    Stock Portfolio Tracker

    Track your stock investments with real-time prices, comprehensive financials, and performance analytics

    Stock Holdings

    Enter ticker symbols and click the search icon to fetch real-time prices and comprehensive financial data from Finnhub

    What Is a Stock Portfolio Tracker?

    A stock portfolio tracker monitors the current value, cost basis, gain/loss, and sector allocation of all your stock holdings in one place. By entering your ticker symbols, share counts, and purchase prices, you can see your total portfolio value, unrealized gains and losses per position, weighted portfolio metrics (P/E ratio, beta, dividend yield), and projected future value at different growth assumptions. Real-time price fetching via Finnhub API keeps your valuations current without manual updates.

    Formula:

    Gain/Loss % = (Current Value − Cost Basis) ÷ Cost Basis × 100

    Portfolio Allocation % = (Position Value ÷ Total Portfolio Value) × 100. Weighted P/E = Sum of (Position P/E × Position Value) ÷ Total Portfolio Value. Understanding both individual position gains and portfolio-level metrics helps you make rebalancing and tax-loss harvesting decisions.

    How to Use This Stock Portfolio Tracker
    1. 1

      Enter a ticker symbol (e.g., AAPL, VTI, SCHD) for each position

    2. 2

      Click the search icon to fetch the current price and financial data from Finnhub

    3. 3

      Enter the number of shares you own

    4. 4

      Enter your purchase price (cost basis per share) for gain/loss calculation

    5. 5

      Add all positions to see total portfolio value, gain/loss, and allocation

    6. 6

      Review the sector allocation chart to identify concentration risk

    7. 7

      Set a projected annual growth rate and time horizon to model future portfolio value

    Why Stock Portfolio Tracker Matters
    • Knowing your exact cost basis per position is essential for tax-loss harvesting and capital gains planning
    • Portfolio allocation drift — positions growing beyond target weights — is the primary trigger for rebalancing
    • Sector concentration risk is invisible without tracking: many investors are unknowingly overweight Tech via index funds plus individual tech stocks
    • Weighted portfolio P/E and beta provide an instant sanity check on whether your portfolio is positioned for your risk tolerance
    • Tracking unrealized gains by position allows you to optimize tax outcomes when selling — prioritizing long-term over short-term gains
    Portfolio Allocation Benchmarks
    Below 5–10%
    Single-stock concentration limit
    Any one stock above 10% creates significant single-stock risk
    Below 25–30%
    Single-sector limit (general)
    Sector overweighting increases correlation risk
    ~10%/year (historical)
    S&P 500 benchmark return
    Long-term average including dividends reinvested
    5% drift
    Rebalancing trigger (common rule)
    Rebalance when any position drifts 5%+ from target allocation
    0.8 – 1.2
    Portfolio beta target (moderate)
    Near-market volatility for balanced risk/return
    Who Should Use a Portfolio Tracker
    • Individual investors managing multiple positions across one or more brokerage accounts
    • Dividend investors tracking income, yield on cost, and reinvestment progress
    • Tax-conscious investors planning year-end tax-loss harvesting and capital gains timing
    • Investors reviewing sector diversification and identifying concentration risks
    • Anyone wanting to project portfolio value at retirement based on current holdings and expected growth
    Common Mistakes to Avoid
    ❌ Not tracking cost basis across all positions
    ✓ Your brokerage tracks cost basis for you, but cross-account and historical positions may require manual entry. Accurate cost basis is essential for tax planning and performance measurement.
    ❌ Ignoring sector concentration
    ✓ Many investors hold broad index funds (heavy in Tech) alongside individual tech stocks — creating a hidden 40–50% Tech allocation. Check sector weights explicitly.
    ❌ Focusing only on individual position returns
    ✓ A position can be down 20% but still be correct to hold based on thesis, valuation, and portfolio context. Track both individual and portfolio-level metrics.
    ❌ Never rebalancing
    ✓ A portfolio that started balanced in 2020 likely has a dramatically different allocation today due to differential performance. Annual rebalancing maintains your intended risk profile.
    💡 Pro Tips
    • •Review portfolio-level beta annually — a portfolio with beta above 1.3 will amplify market downturns by 30%+ relative to the index.
    • •Use the portfolio tracker before year-end to identify tax-loss harvesting opportunities: positions with unrealized losses that can offset realized gains.
    • •Weighted dividend yield gives you a realistic picture of annual dividend income across your entire portfolio, not just high-yield outliers.
    • •Track your portfolio's weighted P/E against the S&P 500 (~21x forward P/E) to assess whether you are holding a premium or discount portfolio.
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    Have questions about using this calculator? Check out our financial guides or contact us for help.

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