Investing calculator
Editor
Enter each purchase lot for the same stock or ETF, then optionally add a current price, dividends, or a target price. Results update instantly so it is easy to track your blended entry price and estimated position metrics.
The purchase lots stay front and center, with optional position metrics grouped below in the same clean card so the calculator stays practical for everyday planning.
Purchase lots
Add the share count, buy price, and optional commission for each lot of the same stock or ETF. Fractional shares are supported.
Each lot contributes to the weighted average share price and the blended cost basis.
Each lot contributes to the weighted average share price and the blended cost basis.
Each lot contributes to the weighted average share price and the blended cost basis.
Position summary inputs
Optional current and target prices help estimate how the position looks today and where it could land at a future exit price.
This average share price calculator is a planning and tracking tool. It estimates weighted average share price, blended cost basis, and position metrics from the values you enter, and it should not be treated as tax advice or broker-authoritative tax lot accounting.
Results
Weighted average share price
$109.17
Total shares owned
30
Total amount invested
$3,275.00
Total fees
$0.00
Blended cost basis / share
$109.17
Break-even price
$109.17
Gross purchase amount
$3,275.00
Current market value
$3,450.00
Unrealized profit/loss
+$175.00
Unrealized return %
+5.34%
Estimated total return incl. dividends
+$175.00
Total invested
$3,275.00
Current market value
$3,450.00
| Lot | Shares | Buy price | Fee | Lot cost basis | % of total shares | % of total invested |
|---|---|---|---|---|---|---|
| Lot 1 | 10 | $100.00 | $0.00 | $1,000.00 | 33.33% | 30.53% |
| Lot 2 | 15 | $120.00 | $0.00 | $1,800.00 | 50% | 54.96% |
| Lot 3 | 5 | $95.00 | $0.00 | $475.00 | 16.67% | 14.5% |
| Totals | 30 | $109.17 | $0.00 | $3,275.00 | 100.00% | 100.00% |
It does not include broker-specific tax lot methods, wash sale handling, stock splits, merger adjustments, or tax advice.
How it works
An average share price calculator combines multiple purchase lots of the same stock or ETF into one blended entry view. It helps you estimate the average stock price paid per share, the total amount invested, and how that position compares with a current or target price.
Weighted average share price is calculated by dividing the total purchase amount for all lots by the total shares owned. Lots with more shares carry more weight in the final number, which is why this result is more useful than taking a simple average of the lot prices.
Blended cost basis means the total amount invested, including lot fees, spread across the total shares owned. That makes it useful for planning because it shows a more complete per-share cost than the weighted average share price alone.
Fees and commissions increase the total amount invested even though they do not buy additional shares. That raises the blended cost basis per share and can move the break-even price higher, which is why it is worth including them when you want a more realistic planning estimate.
When you enter a current market price, the calculator estimates the position's current market value and compares it with the total amount invested to show unrealized profit or loss. Dividends can then be added separately to estimate total return without changing the unrealized price-only result.
This tool is designed for average share price planning and position tracking. It does not replace brokerage records, tax documents, or professional advice, and it should not be treated as tax advice or authoritative multi-lot accounting.