Quick Answer
A portfolio rebalancing planner compares what you hold against a target allocation and tells you exactly what to buy and sell to get back on target. Enter your asset classes, target percentages, and holdings, and this free calculator shows each class’s drift in dollars and percentage points, then builds an exact rebalance plan — full, contribution-first, or tax-aware. Everything runs in your browser, nothing is uploaded, and no account is required.
How It Works
Set your target allocation on the Assets tab — pick a preset (three-fund, age-based, 60/40, all-equity) or add your own classes; targets must total exactly 100%, and Auto-normalize rescales them in one click
Enter holdings on the Holdings tab: asset class, optional ticker, dollar value, optional account label, and a tax-advantaged checkbox — or import a CSV with auto-detected columns, and try “Load sample” for a realistic $182,400 portfolio
Review drift on the Drift tab: current vs target dollars and percent per class, drift in percentage points, and a configurable ±1–10pp band that highlights out-of-band rows
Choose a plan mode — Exact, Contribution-first (new cash goes to underweight classes before anything is sold), or Tax-aware (nothing inside the band is sold; sells prefer tax-advantaged holdings) — and follow the exact buy/sell amounts per holding
Key Facts
- Editable target allocation with presets: three-fund, age-based, 60/40, and all-equity
- Multiple holdings per asset class with optional ticker and account labels, plus a tax-advantaged flag
- Drift table and current-vs-target bar chart with a configurable ±1–10pp drift band
- Three plan modes: exact, contribution-first (new cash directed to underweight classes first), and tax-aware (sells prefer tax-advantaged holdings)
- Tax-aware mode never sells anything inside the drift band and clearly flags forced taxable sells
- All money math uses integer cents, so buys and sells re-sum to the portfolio total exactly
- CSV import with automatic column detection, a header-mapping screen, and per-row error reporting — plus CSV export that round-trips
- One-click realistic $182,400 sample portfolio across 7 holdings
- 100% client-side and free — work is saved in your browser (localStorage), nothing uploaded, no account
Frequently Asked Questions
How does the rebalancing math work?
Every holding is converted to integer cents, so no floating-point drift is possible. Target dollars per class are the largest-remainder split of your total, meaning the target column always re-sums to your portfolio value to the cent. Drift is current minus target in dollars and in percentage points. The plan then trades classes back to target: sells are drawn from your largest holding in each class first, and buys are spread across the class’s holdings in proportion to their size. Contribution-first mode invests new cash into underweight classes (largest shortfall first) before any sell; tax-aware mode only trades classes outside your drift band.
Is this portfolio rebalancing planner free?
Yes — completely free, with no account, no limits, and no watermarks. Portfolio trackers like getquin keep their deeper analytics and guidance behind a paid Premium subscription; this planner does the rebalance trade math — drift, drift bands, contribution-first and tax-aware plans — free in your browser. Your data lives in this browser’s localStorage, so there is also nothing to subscribe to or connect.
Is my portfolio data private?
Yes. The planner runs entirely in your browser with client-side JavaScript: allocations, holdings, and plans are computed locally and never uploaded, logged, or sent to a server. Your work is saved only in this browser’s localStorage so it survives a refresh, and Clear all wipes it. After the page loads you can even go offline and keep working.
What CSV format does the import expect?
Columns: class, ticker, value, account, taxAdvantaged — with a header row. The class name must already exist on the Assets tab (matching is case-insensitive), value is a dollar amount like 12345.67 or $123,455.00, and taxAdvantaged is yes/no (blank means no). Column order does not matter: headers are auto-detected, and if detection is unsure a mapping screen lets you assign each column manually. Rows that fail are listed individually with their line number and reason, and the CSV export uses the same format, so exported files import back unchanged.
Which rebalance mode should I use?
Use Exact when taxes are not a concern and you want everything at target. Use Contribution-first when you have new money to invest: 100% of the contribution goes to underweight classes first (largest drift priority), and only classes still outside the band are traded afterwards — it often fixes drift with no sells at all. Use Tax-aware in taxable accounts: it never sells anything inside your drift band (default ±5 percentage points, adjustable 1–10), and when a class must be sold it draws from tax-advantaged holdings first, clearly flagging any sell forced into taxable holdings.
Is this investment advice?
No. It is an educational calculator: it does arithmetic on the numbers you enter — it does not know your tax bracket, cost basis, fund fees, or goals, and it makes no return projections or recommendations. Treat the output as a starting point and check trades with your broker or a qualified professional before acting, especially where selling could realize capital gains.