Stock Average Calculator

Work out your average cost per share after buying a stock several times. The stock average calculator also shows your profit or loss at the current price.

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Your purchases

Average cost per share
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Estimate only. Not financial advice.

How to use the Stock Average Calculator

  1. For each purchase, enter the Shares and the Price per share. Use Add purchase for more rows.
  2. Optionally, enter the Current share price.
  3. Press Calculate. The average cost per share appears, with total shares, total cost, and your profit or loss.

How it works

average cost = Σ(shares × price) ÷ Σ shares
market value = total shares × current price
profit or loss = market value − total cost

Each purchase counts in proportion to its number of shares, so a large buy moves the average more than a small one.

Examples

  • 100 shares at $50 and 50 shares at $40: $7,000 ÷ 150 = $46.67 average.
  • At a current price of $45, those 150 shares are worth $6,750, a loss of $250 (−3.57%).

Averaging down

Buying more after a price drop lowers your average cost, so a smaller recovery gets you back to break-even. It also puts more money into a position that is already losing. Decide based on the company, not only on the lower average.

Limitations

  • Commissions and fees are not included. Add them to the price per share if you want them counted.
  • Sales are not handled. For tax purposes, cost basis rules such as FIFO may apply.

Frequently asked questions

How is the average stock price calculated?

Multiply shares by price for each purchase, add those totals, and divide by the total number of shares.

Does averaging down work?

It lowers your break-even price, but only helps if the stock recovers.

Can I include fractional shares?

Yes. Enter decimals for shares.

Often used together with the Stock Average Calculator.