Portfolio Rebalancing Calculator
Portfolio Rebalancing
Enter each asset’s name, current market value and target allocation. Select one currency and use it consistently for all asset values. Make sure all target percentages total 100%, enter any additional cash or transaction-cost rate, and select Calculate / Rebalance to view the results.
A Portfolio Rebalancing Calculator helps estimate how much you may need to buy or sell to match your target percentages. This allows you to review your portfolio allocation and plan potential adjustments based on your investment goals and risk tolerance.
Portfolio Rebalancing Calculator
Compare your current holdings with target allocations and estimate the purchases or sales needed to rebalance your portfolio.
Portfolio inputs
Optional; entered in the selected currency.
Applied to combined purchases plus sales. Enter 0 for no estimated fees.
Your assets
2 of 20 assetsEnter all asset values in the same selected currency. Changing the currency does not convert your inputs.
Target allocation total: 100.00% — valid.
Load Example uses hypothetical values for demonstration, not live market data.
Rebalancing results
Enter a current value for each asset, confirm that target allocations total 100%, then select Calculate / Rebalance.
Hypothetical example loaded: values are illustrative and are not live market data.
Current vs target allocation
Bars show each asset's share of the portfolio (0–100%). Current allocation is N/A when the current portfolio value is zero.
Asset-by-asset results
| Asset | Current value | Current allocation | Target allocation | Target value | Buy / sell amount | Allocation difference (pp) |
|---|
Suggested Rebalancing Actions
How fees are estimated: the fee rate is applied to the combined gross value of proposed purchases and sales. Ideal target values and trade amounts are calculated before fees; estimated fees are shown separately and are not deducted from target values.
Important: These are mathematical estimates based on values you enter, not guaranteed investment recommendations. Real trades may be affected by taxes, spreads, minimum order sizes, price movements, and provider-specific fees.
For educational purposes only. No portfolio information is sent or saved by this calculator. Review your own circumstances and consider qualified financial advice before making investment decisions.
What Is Portfolio Rebalancing?
Portfolio rebalancing is the process of adjusting your investments to bring them back to your desired asset allocation. Over time, changes in market prices can cause your portfolio to move away from your original investment targets.
For example, if your target allocation is 60% stocks and 40% bonds, market movements may change these proportions. Rebalancing may involve selling some assets that exceed their target allocation and buying others that fall below it.
How to use the calculator
Enter each asset’s name, current market value and target allocation. Select one currency and use it consistently for all asset values. Make sure all target percentages total 100%, enter any additional cash or transaction-cost rate, and select Calculate / Rebalance to view the results.
4. Formulae aur assumptions
Calculation | Formula |
|---|---|
Current portfolio | Sum of all current asset values |
Portfolio before fees | Current portfolio + additional cash |
Target value | Portfolio before fees × target allocation ÷ 100 |
Buy / sell amount | Target value − current asset value |
Current allocation | Asset value ÷ current portfolio × 100 |
Allocation difference | Current allocation − target allocation, in percentage points |
Estimated fees | (Total purchases + total sales) × fee rate ÷ 100 |
A positive trade is labelled BUY; a negative trade is labelled SELL. Transaction costs are estimated separately and do not reduce the target values. Amounts are displayed to two decimal places, and trades smaller than half a cent are treated as zero to avoid misleading rounding noise.
Changing the currency selector changes how values are labelled and formatted. It does not convert the values into another currency.
5. Testing report
Financial calculations verified in Chromium
An $800/$200 portfolio with 60%/40% targets correctly produces a $200 sale and a $200 purchase. A balanced portfolio produces no trades.
Cash and fees verified
The hypothetical example produces $1,200 in purchases, $700 in sales, and estimated fees of $2.85. A zero-value portfolio with $1,000 additional cash produces $600/$400 target purchases without undefined allocation percentages.
Controls and validation verified
Invalid allocation totals, negative values, negative cash contributions, fees above 100%, Add/Remove, the 20-asset limit, Reset, Load Example and stale-result clearing were tested.
Currency and mobile checks verified
USD, GBP, EUR, CAD and AUD formatting were checked. At a 375px viewport, the page had no overall horizontal overflow. The JavaScript syntax check passed, and the browser tests reported no JavaScript runtime errors.
Important Note
The CST Times Portfolio Rebalancing Calculator provides estimates based on the values and target allocations you enter. It does not fetch live market prices, execute trades, or provide personalised investment advice. Estimated transaction fees may differ from actual costs, and changing the currency selector does not convert your entered values. Always review your investment goals, risk tolerance, and applicable fees before making financial decisions.