Dollar-Cost Averaging Calculator
Enter the prices you bought at to get your dollar-cost averaging cost per share, total shares, current value and gain — with a purchase-by-purchase table.
Dollar-cost averaging (DCA) means investing the same amount at regular intervals instead of trying to time the market. With equal purchases and no fees, more shares are bought at low prices, so average cost is no higher than the simple average price. Irregular purchase amounts or fees change that comparison. Enter your purchases to see the cost basis, current value and return.
How to use this tool
- Enter the amount you invest each time.
- Paste the price for each purchase, one per line. Add a different amount after a space for any irregular purchase.
- Enter today's price (or leave it blank to use the last purchase price) and any fee per trade.
- Read the average cost per share, gain and the purchase table.
Formula
Shares per purchase = (amount − fee) ÷ price
Average cost = total invested ÷ total shares
With equal amounts and no fees, the average cost is the harmonic mean of the prices, which is never higher than their arithmetic mean. That gap is the mathematical effect behind dollar-cost averaging; it does not guarantee a profit if prices fall and stay low.
Example
Investing $500 a month for 12 months at the default prices (from $41.75 to $61.10) puts in $6,000 and buys 118.10 shares. That is an average cost of $50.81 a share, below the $51.52 simple average of the prices. At $62.40 the shares are worth $7,369.32, a gain of $1,369.32 or 22.8%.
Frequently asked questions
Why is my average cost lower than the average price?
Each fixed amount buys extra shares when prices dip, so the cheaper purchases carry more weight. The bigger the price swings, the larger the gap.
Does DCA beat investing all at once?
Not on average when markets rise over time — a lump sum invested earlier is exposed to growth for longer. DCA mainly reduces the regret and risk of investing everything just before a fall. Compare both with the lump sum vs DCA calculator.
Can I use this for crypto or ETFs?
Yes. It works for any asset bought in fractional units. Use the price per coin or per share at each purchase, and include trading fees if you pay them.
This tool gives an estimate for general information only. It is not financial, tax, legal or medical advice — check with a qualified professional before you rely on the result.
Last updated: 2026-10-30