Investment profit and loss
Calculate a completed or hypothetical trade's net gain after entered costs. Enter the actual number of shares or asset units.
Understand the numbers · Make life easier
Portfolio rebalancing amounts
Calculate increases and reductions from your own target percentages, current holdings and optional new contribution. No investment mix is recommended.
Saved in this browser. Before changing devices, export a backup from My tools.
Total amount to increase
20,000
Positive amounts beside item names mean increase; negative amounts mean reduce. These differences follow your own targets and are not investment recommendations. Use one currency; expand details for current and target amounts.
Total amount to reduce20,000
New contribution0
Total after contribution100,000
A-20,000
B20,000
Worked steps
- 100000 + 0 = 100000
- 100000 × 60% = 60000
- 100000 × 40% = 40000
Calculation details (2 rows)
| Item name | Current amount | Target (%) | Target amount | Difference (+ increase, - reduce) |
|---|---|---|---|---|
| A | 80,000 | 60 | 60,000 | -20,000 |
| B | 20,000 | 40 | 40,000 | 20,000 |
Use one currency. Targets must total 100%, with up to four decimal places. Total after contribution = current total + new contribution; each target amount = total × target percentage; difference = target minus current amount. Positive means increase, negative means reduce. Displayed values may have rounding differences. These are calculations from your own targets, not investment, product or timing recommendations. Fees, taxes, share sizes and minimum trades are excluded. Withdrawals, leverage and buy-only optimization are not modeled.
Method and scope
Use one currency and your own target percentages totaling 100%. Total after contribution = current total + new contribution. Target amount = that total × target percentage.
Difference = target amount minus current amount. Positive means increase and negative means reduce. Rounding differences may appear.
This is arithmetic from your own targets, not an investment recommendation. Fees, taxes, share sizes, trading limits, withdrawals, leverage and buy-only optimization are excluded.
What this helps you do
This tool helps when you have already chosen target percentages and want to calculate the amount each holding would need. It does not choose investments, suitable allocations or trading times, and does not forecast returns.
What to enter
Enter a name, current value and your target percentage for each item. Simple names such as A and B are enough; no account details are needed. Use one currency throughout. Percentages must total 100; enter 60 for 60%, not 0.6. Enter fresh money once in the additional contribution field. The 60/40 example is editable and is not a recommended allocation.
How the calculation works
Add the current values and the new contribution. Multiply that total by each target percentage, then subtract the current value to obtain each difference. Total increases minus total reductions should equal the new contribution.
Worked example
With A at 80000 and B at 20000 and targets of 60% and 40%, no new contribution gives target values of 60000 and 40000: differences of -20000 and +20000. Adding 20000 raises the total to 120000 and the targets to 72000 and 48000. A then decreases by 8000 and B increases by 28000, a net addition of 20000.
Understanding the answer
The main answer totals the positive differences. It can exceed your new contribution because amounts reduced elsewhere can also fund increases. A positive amount beside an item means increase; a negative amount means reduce. Expand the details to check current and target amounts. Zero means no change under your assumptions.
Scope and limitations
Use 2 to 20 items, each current value and new contribution at most one billion. Targets may have up to four decimal places and must total 100%. Zero holdings and zero targets are supported, but the total must be positive. Fees, taxes, share rounding, trading limits and price changes are excluded. Displayed values may have rounding differences and are not trade instructions. No buy-only optimization, withdrawals or leverage is modeled. Saved data stays in this browser.