Stock Calculator
Enter your shares, prices, and commissions. The tool computes net buy/sell price, profit, ROI%, break-even selling price, and the share result — all in real time. Export a PDF.
Scales change the display while preserving underlying math.
🧾Number of shares ?
Shares must be ≥ 0.
🛒Purchase of shares
💵Buying price ?
$
Buying price must be ≥ 0.
🧾Buying commission ?
$
%
🧮Net buying price ?
$
🏷️Selling shares
💸Selling price ?
$
Selling price must be ≥ 0.
🧾Selling commission ?
$
%
🧾Net selling price ?
$
📊Investment performance
Profit
—
Return on investment (ROI)
—
Break-even selling price
—
⚡Quick summary
—
📌Share result
🧮Step-by-step derivation
Profit formula:
Profit = [(SP × No) − SC] − [(BP × No) + BC]
ROI:
ROI = Profit ÷ [(BP × No) + BC]
Break-even selling price (per share):
BE = ( (BP × No) + BC + SCfixed ) ÷ ( No × (1 − SC%) )
Substitute: …
Solve: …
📚Reference table & sources
TopicSummarySource
Profit with commissions Profit = [(SP × No) − SC] − [(BP × No) + BC] Investopedia — Stock Gains & Losses
ROI ROI = Profit / Total Cost Investopedia — Return on Investment
Break-even concept Price where net proceeds = total cost; include fixed and % commissions. SEC — Fees & Commissions
Links are for background reading; the calculator computes directly.