Financial calculator
Portfolio Rebalancing Calculator
Enter your current holdings and target weights to see how far each position has drifted and the buy/sell amounts needed to return to your target allocation — for two assets, a 60/40 split, or a full ETF portfolio.
How to use this calculator
Enter each holding's current value and your own target weight; add optional new cash. The table shows current vs target weight, the drift in percentage points, and the simulated trade to reach each target. All figures are illustrative arithmetic based only on the values you enter.
Inputs are editable, results update locally in the browser, and outputs are informational arithmetic based only on the values and targets you enter. The buy/sell amounts show what would bring each position back to your chosen target weight — they are not a recommendation to trade any security.
How portfolio rebalancing works
Rebalancing means moving each holding back to its target weight after market moves push it off. The math is simple: a holding's target dollar value is the whole portfolio value times that holding's target weight, and the trade is the difference between that target value and what you hold now.
This calculator does that for every row at once. The Drift column is each position's current weight minus its target, in percentage points, so you can see at a glance which holdings have run ahead and which have fallen behind.
Calendar vs threshold (band) rebalancing
Calendar rebalancing trades on a fixed schedule — quarterly or yearly. Threshold (band) rebalancing only trades when a holding drifts past a tolerance you pick, such as 5 percentage points, which can mean fewer trades.
Because the Drift column shows each gap in percentage points, you can use either approach: rebalance everything on your schedule, or act only on the rows whose drift exceeds your band.
Rebalance with new contributions instead of selling
Selling to rebalance can realize gains and taxes in a taxable account. Entering an amount in 'New cash to add' funds the most underweight positions first, so you can steer the portfolio back toward target by buying rather than selling.
This pairs with dollar-cost averaging: each new contribution both adds money and nudges the allocation back toward plan.
Data notice: Market data may be delayed, incomplete, or unavailable for some securities. Metrics are provided for informational purposes only.
Last updated:
Calculator notes
- The calculator runs in the browser and keeps the assumptions visible to the reader.
- Inputs are transparent and editable, which makes the assumptions visible to the reader.
- Results are estimates for informational purposes and can be compared with stock and ETF research pages.
Financial disclaimer
This website provides informational content only and is not financial advice. We do not recommend buying or selling securities. Market data may be delayed, incomplete, or inaccurate. Always verify information with official sources before making financial decisions.
Related stock and ETF pages
FAQ
How do I rebalance a two-asset portfolio?
Enter both holdings with their current values and target percentages (for example 60 and 40). The calculator shows how far each has drifted and the exact amount to buy or sell to return to your two-asset target.
How do I rebalance a 60/40 portfolio?
Set one asset's target to 60 and the other to 40, enter current values, and the table returns the buy/sell needed to restore the 60/40 split. Add new cash to rebalance with contributions instead of selling.
What is threshold rebalancing?
Threshold (band) rebalancing means you only trade when a holding drifts beyond a tolerance you choose, instead of on a fixed calendar. The Drift column shows each position's gap in percentage points so you can apply your own threshold.
Can I rebalance with new contributions instead of selling?
Yes. Enter an amount in 'New cash to add' and the calculator directs it to the underweight positions first, so you can rebalance by buying rather than selling.
Does this work for an ETF portfolio?
Yes. Enter any tickers — ETFs, stocks, or funds. The arithmetic is identical: current value versus target weight, the drift, and the trade that closes the gap.