Average Price Calculator

Average Price
Total Shares
Total Amount

How to use

Stock Average Price Calculator is a tool for averaging the price of stocks. Enter the price and the number of shares to get the average cost.

  • Enter the purchase price and the number of shares to calculate average unit price automatically.
  • Click the button to add an item.
  • Click the button to delete the item.
  • Click the button to save the current item to the web browser.

If you clear your browser's data, stored data may be lost. Click the > Export to back up or migrate your saved data.

How it works

To find the average stock price, it first calculates the total purchase price, then divides by the number of shares.

  1. Total purchase price = Σ(Price of stock * Number of shares)
  2. Total shares = Σ(Number of shares)
  3. Average price = Total purchase price / Total shares

For example, suppose you currently own 100 shares at a price of 100, and you want to buy 200 shares at a new price of 200. In this case, the total purchase price is 100x100 + 200x200 = 50000. Dividing this by the total number of shares is 50000 / 300 ≈ 167. So, the average price of the stock is about 167.


In general, good companies tend to rise in stock prices over the long term, and bad companies tend to fall over the long term. If you buy more shares just because the stock price has gone down, you may be investing more money in a bad company. Therefore, it is necessary to carefully assess whether the current stock price is truely undervalued by analyzing the company's future vision and current fundamentals.