Stock Price Average Calculator
Compute the weighted average cost per share across up to three separate purchase lots.
Results
What is it?
The stock price average calculator (also known as a cost-basis calculator) computes the weighted average cost per share when you have purchased the same stock at different prices across multiple transactions. It is essential for tracking your true cost basis.
How to use
Enter the purchase price and number of shares for up to three lots. If you only have two purchases, leave the third lot fields at zero. The calculator computes the total investment, total shares, and weighted average price.
Example scenario
You bought 100 shares at $50, then 150 at $45, then 200 at $40. Total invested = $5,000 + $6,750 + $8,000 = $19,750. Total shares = 450. Average price = $19,750 / 450 ≈ $43.89.
Pro tip
Dollar-cost averaging (buying at regular intervals regardless of price) naturally lowers your average cost during volatile markets, since you buy more shares when prices are low and fewer when prices are high.