Prepared by StockDCA · Revised September 13, 2026 · This guide describes the current calculator, not a brokerage account.
Get started with the calculator
Looking for company research, AI reading plans or Notebook? Start with the workspace guide. The steps below cover the original calculator.
To understand the company reports behind your research, browse the financial statement and SEC filing guides. Those guides explain reported business results; this page explains calculations from your own inputs.
This guide focuses only on using the StockDCA Calculator. You will see
exactly where to enter each number and what the calculator displays as
your inputs change. There is no separate calculate button—the results
update automatically.
Start with a known answer
Open this fictional example: 2.5 shares at $100, five at $80 and 1.25 at $120. Expected results are $800 total purchase cost, 8.75 shares and $91.43 average cost. With current price $100, market value is $875 and the price-based gain is $75 (9.38%).
Use one ticker and one currency. StockDCA does not fetch live prices, forecast investment growth or combine a multi-asset portfolio. Compare your entries with execution records, not merely an intended order amount.
1
Step 1
Enter your purchases
Start by entering each purchase as its own row in the calculator.
Every row has two fields:
Purchase price ($) and Shares bought.
| Field |
What to enter |
Example |
| Purchase price ($) |
The price paid per share for that purchase. |
$100 |
| Shares bought |
The number of shares purchased at that price. |
2.5 |
To record another transaction, click ＋ Add purchase.
A new row will appear for the next purchase. To delete a row, click
its corresponding Remove purchase N button, where
N identifies the purchase row.
Tip: Enter purchases separately instead of combining
them. This lets the calculator use the price and share count from
every transaction.
2
Step 2
Check your average cost
As soon as you enter or edit a purchase, the calculator updates the
summary automatically. You do not need to click a calculate button.
Look for these three results:
| Result |
What it shows |
| Average cost per share |
The average amount invested for each share across all entered purchases. |
| Total invested |
The total dollar amount represented by the purchase rows you entered. |
| Total shares |
The combined number of shares from all purchase rows. |
If you change a purchase price, change the number of shares, add a
row, or remove a row, all three values recalculate immediately.
Check that the purchase rows match your records before using the
summary.
3
Step 3
Add the current price (optional)
To review the current position, enter a value in
Current share price (optional). Once a current price
is entered, the calculator displays:
- Market value: the current value of the entered share position.
- Profit/Loss: the result shown as both a dollar amount and a percentage.
You can update the current share price whenever you want to test a
different price. Leave this field blank if you only want to review
your purchase totals and average cost.
Tip: The current price field is optional. It is not
required for the calculator to show Average cost per share, Total
invested, or Total shares.
4
Step 4
Model a sale (optional)
Use the optional Sell calculator when you want to
model selling part or all of the entered position. Fill in:
- Sell price: the price per share you want to test.
- Shares sold: the number of shares you want to sell.
After you enter these values, the calculator shows the
remaining position and the
average-cost estimated gain/loss for the modeled sale. Adjust
either input to compare different sale prices or share quantities.
Tip: Keep the sell quantity within the number of
shares entered in your purchase rows when modeling a partial or full
sale.
Why the sale result is an average-cost estimate
Suppose you bought 10 shares at $100 and 10 at $60. The entered purchase cost is $1,600 for 20 shares, or $80 per share. Modeling a sale of five shares at $90 gives $450 proceeds, $400 allocated average cost and a $50 estimated gain. The modeled remaining position is 15 shares at $1,200 average-based cost.
Same hypothetical sale, different cost assumptions| Illustrative method | Cost assigned to five shares | Proceeds | Gain / loss |
|---|
| StockDCA weighted-average estimate | 5 × $80 = $400 | $450 | +$50 |
| FIFO illustration: first purchase sold first | 5 × $100 = $500 | $450 | −$50 |
Load the average-cost sale example. The tool does not offer FIFO or choose a lot for your broker; that second row explains why results can differ.
For U.S. tax reporting, specific-share identification or FIFO may apply. Average basis has limited eligibility, including certain fund and reinvestment-plan holdings. Check the IRS cost-basis FAQ and your broker's records. This estimate is not a tax calculation.
The sale panel is a separate what-if calculation. It does not remove the sold shares from the purchase rows, execute an order or maintain a transaction ledger. The main position metrics continue to describe the entered purchases.
5
Step 5
Save or share your results
Click Copy share link to generate a URL from your current entries and copy it.
Resolve any invalid or incomplete input before sharing.
New links store values after # rather than in the server request. Opening a link loads its values and removes them from the address bar. To save or share again, use Copy share link; copying the cleaned address or reloading it will not retain the imported values. Older ?data= links remain supported, but their initial request can be logged by the hosting provider.
- Finish entering your purchases and any optional price or sale inputs.
- Click Copy share link to generate and copy the link.
- If clipboard access is blocked, select and copy the URL in the field manually.
- Review what you are sharing, then save the link or send it only to people you trust.
Before sharing, review the link and make sure it contains only the
information you intend to share.
Incomplete rows and limits
A completely blank purchase row is ignored. If a row contains only a price or only a quantity, complete it or remove it; the calculator pauses the estimate instead of assuming the missing value is zero. A price may be zero when that is genuinely your known purchase cost, but a populated purchase must have more than zero shares. Transfers and gifted holdings may require different basis information.
Negative, malformed and overflowing values are rejected. Up to 200 purchase rows can be entered. An incomplete sale needs both fields, and shares sold cannot exceed entered shares. A zero purchase cost has no defined percentage return, so that percentage displays N/A.
Share links encode values; they do not encrypt them. Anyone receiving a link can read its inputs, and opened URLs may appear in history or server logs. Do not share sensitive portfolio information. If automatic clipboard access is blocked, select and copy the generated URL manually.
Quick tips for using the calculator
Load example
Click Load example to populate the calculator
with sample data and try the controls before entering your own
purchases.
Clear all
Click Clear all to remove the entered data and
start over with a blank calculator.
Use fractional shares
The calculator supports decimal share amounts, such as
0.5 or 1.25, for fractional-share
purchases.
Frequently asked questions
Is the StockDCA Calculator free?
Yes. The StockDCA Calculator is available to use without a paid
subscription.
Can the calculator handle fractional shares?
Yes. You can enter fractional shares, such as 0.5 or 1.25, when
your brokerage supports fractional-share purchases.
Is my calculator data safe?
Do not enter private account credentials or sensitive personal
information. Before sharing a generated URL, review it and share
it only with people you trust.
How do I share my calculator results?
The calculator generates a Shareable URL when you click Copy share link. Click
Copy share link to copy the link, then save it or send it to
someone else.
Ready to try it?
Enter your purchases, check the automatically calculated position,
and test current or potential sale prices in the StockDCA Calculator.
Open the StockDCA Calculator