Tax Harvest Planner Calculator
Compare an entered gain allowance with realized gains, then review theoretical allowance value and positive lot gain allocations.
Allowance Room or Gain Assigned
$2,500.00
Theoretical Allowance Value
$500.00
| Ticker | Gain | Allowance Room or Gain Assigned |
|---|---|---|
| AAPL | $4,000.00 | $2,500.00 |
How It Works
Enter the gain allowance, realized gains, and marginal rate. For each lot, enter its ticker, share count, cost basis per share, and current price per share. The calculator subtracts realized gains from the allowance, then lists lots with positive gains in descending order.
The results show allowance room and theoretical allowance value. The table lists each positive lot gain and its assigned amount. A lot can be partly allocated, and the table does not calculate a share quantity to sell.
Only lots with positive gains appear in the table. The calculation does not include losses or identify whether a lot qualifies for any tax treatment.
Use the figures to inspect a generic allowance scenario. The entered allowance, rate, and lot inputs do not establish which tax rules apply.
Step by step
- Enter an allowance, realized gains, marginal rate, and lot details
- Review remaining allowance, theoretical allowance value, and positive lot gains
- Read each lot amount as a gain allocation, not a number of shares to sell
Worked example
Enter a $3,000 gain allowance, $500 in gains already realized, and a 20% marginal rate. Add one lot with 10 shares, a $100 cost basis per share, and a current price of $120. The lot has a $200 gain.
The remaining allowance is $2,500 and the theoretical allowance value is $500. The lot table shows the $200 gain and assigns $200 of it to the allowance. The value uses all remaining allowance even though the lot gain is only $200. The assigned amount is a gain allocation, not a share quantity or an executable order.
When to use this calculator
Use this planner to compare an entered gain allowance with gains already realized and to see how positive lot gains are allocated against the remaining amount.
Use a separate, jurisdiction specific source or calculation to determine applicable tax rules, then treat this page as generic arithmetic rather than an execution plan.
Common mistakes
Reading theoretical allowance value as realized tax savings overstates what the output means. It can remain positive when no profitable lots are entered because it uses all unused allowance.
Entering cost basis as the full lot cost instead of cost per share changes the calculated gain. The input is multiplied by the entered share count.
The Formula
Allowance room = max(0, Gain allowance − Realized gains)
Theoretical allowance value = Allowance room × (Marginal rate / 100)
Lot gain = (Current price − Cost basis per share) × Shares
Allocate positive lot gains from largest to smallest, up to the allowance room
Rows are sorted by lot gain from largest to smallest. Each allocation is capped at the lot’s full gain and the remaining allowance.
Limitations and assumptions
This is generic allowance arithmetic, not a jurisdiction specific tax calculation. It does not model eligibility, holding period rules, losses, repurchases, transaction costs, or tax reporting. The lot table assigns currency amounts and does not calculate share quantities to sell or account for fractional share restrictions.
Key terms
- Gain allowance
- The gain amount entered for this simplified allowance calculation. The calculator does not determine whether it is available under local tax rules.
- Realized gains
- The gain amount entered as already realized. It is subtracted from the entered allowance to calculate remaining room.
- Theoretical allowance value
- Remaining allowance multiplied by the entered marginal rate. It is calculated independently of profitable lot gains and is not realized tax savings.
Compare alternatives
This planner uses a user entered gain allowance and rate. The Capital Gains Holding Period Calculator compares holding period assumptions, the Tax Bracket Calculator covers United States federal ordinary income brackets, and the Accumulating vs Distributing ETF Calculator compares fund structures. The Wash Sale Alert Calculator covers a separate issue for loss sales; this planner does not apply wash sale rules.
Review allowance room and theoretical allowance value, then inspect positive lot gains and the amount assigned to each. This calculation does not determine whether a gain qualifies for an allowance under any jurisdiction’s rules.
FAQ
What does the planner calculate?
Enter a gain allowance, gains already realized, a marginal rate, and lots with share count, cost basis per share, and current price per share. The calculator reports remaining allowance, theoretical allowance value, and positive lot gains ranked from largest to smallest with an amount assigned against the allowance.
Does theoretical allowance value depend on profitable lots?
No. It multiplies the entire unused allowance by the entered marginal rate, even when there are no profitable lots. Treat it as a theoretical allowance value, not tax saved or a prediction of a tax bill.
How are lot gains and allocations calculated?
For each lot, the calculator multiplies current price minus cost basis per share by the number of shares. It keeps positive gains, ranks them from largest to smallest, and assigns each up to the remaining allowance. A row can show a partial gain allocation without calculating how many shares would need to be sold.
Does this apply tax rules for my country?
No. It applies generic arithmetic to the allowance and rate you enter. It does not model the tax rules, eligibility tests, holding periods, loss offsets, repurchase rules, or reporting requirements of a particular jurisdiction.
Does the lot table tell me how many shares to sell?
No. The table allocates a dollar amount of gain against the remaining allowance. It does not convert that amount into shares to sell or generate an order. The share count entered describes the full lot used to calculate its gain.
Related Tools
For separate questions, use the Capital Gains Holding Period Calculator to compare holding period assumptions, the Tax Bracket Calculator for United States federal ordinary income brackets, and the Accumulating vs Distributing ETF Calculator to compare fund structures. The Wash Sale Alert Calculator covers loss sale scenarios, which this gain allowance model does not handle.