About the Average Price Calculator
Calculate the average price of a stock or crypto you bought in several purchases, including fees. Then see how many more you'd need to buy at today's price to bring your average down (or up) to a target.
Useful for dollar-cost averaging, averaging down on a falling position and keeping track of your real break-even price.
How it works
The average is the total amount you paid, quantity times price for each purchase plus any fees, divided by the total quantity. Two buys of 100 shares at $10 and $8 average $9, but 50 at $20 and 150 at $16 average $17, because the bigger purchase counts more.
To reach a target average by buying at a given price, the quantity needed is your current quantity times (current average − target) divided by (target − buy price). The target has to lie between your average and the price you can buy at.
Assumptions and limits
- Fees entered for a purchase are added to its cost.
- Sales aren't included: enter only the purchases you still hold.
- For planning only, not financial advice.
Worked examples
Two purchases
100 shares at $10 and 100 at $8: average $9 on 200 shares.
Averaging down
Holding 100 at an average of $50 with the price at $40, buying 100 more brings the average to $45.
Crypto in parts
0.5 BTC at $60,000 and 0.25 BTC at $48,000 average $56,000.
How to use the Average Price Calculator
- Enter each purchase. Quantity, price and fee.
- Read your average. Your break-even price.
- Plan the next buy. Quantity to reach a target average.
Frequently asked questions
How do I calculate my average share price?
Add up what you paid for every purchase, including fees, and divide by the total number of shares. The result is the price at which selling everything would break even before selling fees.
How many shares do I need to average down?
Enter the price you can buy at and the average you want. The tool works out the quantity from your current holding; the further the target from your average, the more you need to buy.
Why can't I reach any average I like?
Buying at $40 can bring a $50 average closer to $40 but never below it. The target must lie between your current average and the price you can buy at now.
Should fees be included?
Yes, if you want your true break-even price. Fees add to what each purchase cost, so including them gives a slightly higher and more honest average than the prices alone.
Does it work for crypto with decimals?
Yes. Quantities can have decimals, such as 0.25 BTC or 1.5 ETH, and the average is calculated exactly without rounding until it's shown on the page.
This tool runs entirely in your browser. What you enter or upload stays on your device and is never sent to our servers.