How the Price Per Share Calculator works
This tool answers a question every investor eventually asks: what did I actually pay per share? It uses the standard average-cost-basis formula, folding your total investment and any broker fees into a single per-share figure, then compares that cost basis against the current market price to show your value, gain, or loss.
The formula
For a total amount invested, any fees or commissions paid, and the number of shares purchased, the price per share (cost basis) is:
Price Per Share = (Amount Invested + Fees) / Shares Purchased
Fees are added to the numerator because they are part of what it actually cost you to acquire the shares. Once you have the price per share, the calculator multiplies your shares by the current market price to get the holding's current value, then subtracts total cost to get your gain or loss in dollars and as a percentage.
Worked example
Invest $5,000 in a stock, pay $10 in brokerage fees, and receive 200 shares. Total cost is $5,010, so the price per share is $5,010 / 200 = $25.05 per share. If the stock later trades at $30 per share, your 200 shares are worth $6,000. That is a gain of $6,000 − $5,010 = $990, or about 19.76% on your total cost.
What moves the result most
- Number of shares purchased: spreading the same dollar amount across more shares lowers the price per share; fewer shares raises it.
- Fees and commissions: on smaller trades, even a modest flat fee can move the effective price per share noticeably — a $10 fee on a $500 purchase is a 2% add-on.
- Current price versus cost basis: the gap between what you paid and what the shares are worth now is what drives your gain or loss, both in dollars and in percentage terms.
Blended price across multiple purchases
If you bought shares in several lots at different prices — common with dollar-cost averaging or dividend reinvestment — this calculator can still help: add up the total dollars spent (including all fees) across every lot, and enter the total number of shares acquired. Dividing the two gives your true weighted-average price per share, which is the figure typically used for cost-basis and capital-gains purposes.