Last updated: March 2026
Why Track Your Stock Portfolio?
Knowing exactly where your money is invested — and how each position is performing — is the foundation of smart investing. Yet many investors rely on a patchwork of brokerage apps, spreadsheets, and mental math. A dedicated portfolio tracker gives you a unified view of your entire investment picture, regardless of which brokerages hold your shares.
This tracker calculates gain/loss for each position and your overall portfolio, both in dollar terms and percentage. Green rows show positions in profit; red rows show losses. Click any row to see individual lots — when you bought, how many days you have held, and the gain/loss on each purchase.
The allocation donut chart reveals portfolio concentration at a glance. Financial advisors typically recommend no single stock exceeds 5-10% of your portfolio. If one position has grown to 30-40% of your total, it may be time to rebalance — taking some profits and diversifying into other holdings.
The watchlist lets you track stocks you are interested in buying, with target prices. When a stock dips below your target, you will see an alert badge — helping you stay disciplined about buying at the right price instead of chasing momentum.
Unlike cloud-based portfolio trackers, all your data stays in your browser. Nothing is transmitted to any server. This means total privacy for your financial data. Export to CSV or JSON anytime for backup or spreadsheet analysis.
Frequently Asked Questions
Is my portfolio data safe and private?
Yes. All your portfolio data is stored exclusively in your browser's localStorage. Nothing is ever sent to any server. Your holdings, watchlist, and settings never leave your device. You can export your data anytime as CSV or JSON for backup.
Can I track fractional shares?
Yes. The tracker supports fractional shares down to four decimal places, which is common with services like Robinhood, M1 Finance, Fidelity, and Schwab that offer fractional share purchasing. Enter any decimal amount (e.g., 0.5 shares of AMZN).
How do I update stock prices?
Click the 'Update Prices' button to manually enter current prices for each ticker in your portfolio. Since this tool runs entirely in your browser with no API connections, prices are updated manually. This keeps your data completely private.
Can I import my existing portfolio?
Yes. Click 'Import CSV' and upload a CSV file with columns for ticker (or symbol), shares (or quantity), purchase_price (or cost/price), and optionally purchase_date. The importer is flexible with column naming and will match common variations.
How is gain/loss calculated?
Gain/loss is calculated as (Current Price - Purchase Price) x Shares for each position. When you have multiple lots of the same ticker (bought at different prices/dates), the table shows the weighted average cost and total gain/loss. Click any row to see individual lot details.
What does the allocation chart show?
The donut chart shows your portfolio weight by holding — what percentage of your total portfolio value each stock represents. This helps you identify concentration risk and decide when to rebalance. A well-diversified portfolio typically has no single position above 10-15%.