Stock Average Calculator
Find your average cost per share and total cost basis across multiple stock purchases.
Independently verified for accuracy
Calculator by Toolsloft ↗- Total shares
- 150
- Total cost
- 8000
- Average cost
- 53.33
This calculator finds your average cost per share across several purchases of the same stock. Enter the shares and price for each buy and it returns the total shares, the total amount invested, and the blended cost basis. Use it when you have been adding to a position and want a single break-even price.
How this is calculated
The average cost is the total amount invested divided by the total shares held. Total invested is the sum of shares times price for each purchase, which is the standard weighted-average cost basis.
How to use
- Enter the shares and price for your first purchase.
- Add a row for each additional purchase of the same stock.
- Read the total shares, total cost, and average cost per share.
Examples
- 100 @ $50 and 50 @ $60:
average cost $53.33 - 10 @ $200, 20 @ $180, 5 @ $220:
average cost $191.43
FAQ
- How is the average cost calculated?
- It is the total amount invested divided by the total number of shares, which weights each price by how many shares you bought at it. A simple average of the prices would ignore the share counts.
- What is a cost basis used for?
- Your cost basis is the price the broker and the tax authority use to measure gain or loss when you sell. Averaging across purchases gives the basis per share for the whole position.
- Does this include commissions?
- No. Enter the net price you paid per share. If you want commissions included, add them into the price for that purchase.