Calculator
Add assets and their current values. Targets are optional. Cash flow lets you plan an additional deposit or a withdrawal.
Example data table
| Asset | Value | Target % |
|---|---|---|
| Global Equity | 15000 | 55 |
| Investment Grade Bonds | 9000 | 35 |
| Cash | 2500 | 10 |
Enter the same rows in the calculator to see weights, drift, and rebalancing.
Formula used
- Total value: T = Σ Vi
- Current percentage: Pi = (Vi / T) × 100
- Total after cash flow: T' = T + C
- Target value: Vi* = (Gi / 100) × T'
- Drift: Di = Pi − Gi
- Rebalance amount: Ri = Vi* − Vi
- Concentration index (HHI): H = Σ (Vi / T)²
- Effective holdings: Neff = 1 / H
If target percentages do not sum to 100, they are normalized before computing targets and rebalancing.
How to use this calculator
- Enter a currency symbol and preferred decimal places.
- Add each asset name and its current value.
- Optionally enter target percentages for each asset.
- Optionally enter cash flow to plan deposits or withdrawals.
- Click Calculate to view results above the form.
- Use the rebalance column to guide buys or sells.
- Download CSV or PDF for reporting and sharing.
FAQs
1) What does portfolio percentage mean?
It is the share of total portfolio value held in an asset. The calculator divides each asset value by the total and converts it into a percentage.
2) Do I need targets to use this tool?
No. If targets are blank, the calculator still shows current percentages. Drift and rebalancing fields appear only when targets are provided.
3) What happens if targets do not add to 100%?
The calculator can normalize the targets so they behave like a full allocation plan. It rescales targets proportionally and then computes drift and rebalancing.
4) How is the rebalance amount calculated?
It computes a target value for each asset using the total after cash flow. Rebalance equals target value minus current value, indicating buy or sell direction.
5) What is planned cash flow used for?
Cash flow lets you model a deposit or withdrawal before rebalancing. A positive number adds money and a negative number reduces the total used in target calculations.
6) What is the concentration index shown in results?
It is a concentration measure based on squared portfolio fractions. Higher values mean fewer dominant holdings. The effective holdings estimate converts it into an intuitive count.
7) Can I include assets with zero value?
You can, but they will not change the total and their percentage will be zero. For clean results, omit unused rows or remove them with the link.
8) Are CSV and PDF exports identical to the table?
They include the same key fields from the results table. CSV is best for spreadsheets, while the PDF is a compact report for sharing and archiving.