Stock Average Calculator
Calculate your average cost per share across multiple stock purchases.
Stock Average Cost Basis
When you buy the same stock at different prices over time, your average cost per share is the total amount invested divided by the total number of shares. This is your cost basis, which determines your profit or loss when you sell. Fill in as many purchases as you need (unused rows are ignored).
The formula is: Average Cost = Total Invested / Total Shares, where Total Invested is the sum of (Price x Shares) for each purchase.
Frequently Asked Questions
What is average cost per share?
Average cost per share is the total amount you have spent on a stock divided by the total number of shares you own. It represents your breakeven price. If the stock is trading above your average cost, you are in profit. If it is below, you are at a loss.
Why would you average down on a stock?
Averaging down means buying more shares after the price drops, which lowers your overall average cost. This can be a good strategy if you believe the stock will recover, because you need a smaller rebound to break even. However, it also increases your total exposure to a stock that may keep falling.
What is dollar cost averaging?
Dollar cost averaging means investing a fixed dollar amount on a regular schedule regardless of the price. When prices are low, you buy more shares; when prices are high, you buy fewer. Over time, this tends to produce a lower average cost than trying to time the market.
When is this calculator useful?
Use this calculator anytime you have made multiple purchases of the same stock at different prices and want to know your overall cost basis. It is especially helpful for tax reporting, evaluating your position, or deciding whether to add to or reduce your holdings.
What are the risks of averaging down?
The biggest risk is that the stock continues to decline, and you end up with a larger loss on a bigger position. Averaging down on a fundamentally broken company can lead to significant losses. Only average down if your original investment thesis is still intact and you can afford the additional risk.