Portfolio rebalancing calculator
Enter what each holding is worth today and its target weight. The calculator shows how far each one has drifted and exactly how much to buy or sell, or how to rebalance using only new money, without selling.
- US stocks (e.g. VTI)No trade
60.2% now → 57.4% after · target 50.0%· +10.2 pp over limit
- International stocks (e.g. VXUS)Buy 400
17.5% now → 17.0% after · target 20.0%
- Bonds (e.g. BND)Buy 3,000
19.4% now → 21.3% after · target 25.0%· −5.6 pp over limit
- Gold (e.g. GLD)Buy 1,600
2.9% now → 4.3% after · target 5.0%
Portfolio 103,000 now, 108,000 after the new money. Total traded: 5,000. 2 holdings are more than 5 points from target. New money alone is not enough to reach every target; switch to “Buy and sell” to close the gap fully.
Amounts in your own currency. Taxes, trading costs and minimum lot sizes are not included. Runs in your browser: nothing you type is sent or stored.
Two ways to rebalance
Buy and sell: every holding goes back exactly to its target. It is the quickest way back to the risk you chose, but selling can realise taxable gains and adds trading costs.
New money only: contributions go to the most underweight holdings first and nothing is sold. For anyone who invests every month this keeps the portfolio close to target with no sales at all; a large drift may need more than one contribution to close.
Questions
What does rebalancing a portfolio mean?
Bringing each holding back to its target weight. Over time the assets that rose grow beyond their share and the ones that fell shrink, so the portfolio drifts away from the risk you chose. Rebalancing sells part of what grew and buys what lagged, or directs new money to what is underweight.
How does “new money only” work?
The new contribution goes to the holdings that are furthest below target first, so you move closer to your weights without selling anything, which avoids realising gains and paying trading costs on sales. If the contribution is not enough to close the whole gap, the calculator tells you; a withdrawal works the other way round, taking money from the most overweight holdings first.
How often should I rebalance?
Common approaches are once a year, or only when a holding drifts more than a set number of percentage points from its target (for example 5). Rebalancing more often adds costs and taxes without a clear benefit. The drift alert in the calculator flags the holdings beyond your limit.
Does the calculator include taxes and fees?
No. Selling can trigger capital gains tax and every trade can carry a commission or spread, depending on your country and broker. The calculator works on amounts only and runs entirely in your browser: nothing you type is sent or stored.