Dollar cost averaging calculator: total invested, ending value and average cost per share
Investing the same amount at regular intervals for 10 years at $200 a month puts in $24,000, and the ending value depends on the return you assume. Enter an amount, how often, the years and an assumed annual return, or switch to price path mode and type the price at each purchase to see the shares bought and your average cost. Dollar-cost averaging does not guarantee a gain, and this calculator makes no forecast. For a comparison against a savings rate, see the high-yield savings calculator.
Dollar cost averaging calculator
Ending value if the assumed return holds every year:
$32,652.86
Total invested $24,000.00 over 120 payments; difference $8,652.86.
| Year | Invested to date | Balance at end of period |
|---|---|---|
| 1 | $2,400.00 | $2,477.31 |
| 2 | $4,800.00 | $5,103.25 |
| 3 | $7,200.00 | $7,886.75 |
| 4 | $9,600.00 | $10,837.26 |
| 5 | $12,000.00 | $13,964.80 |
| 6 | $14,400.00 | $17,280.00 |
| 7 | $16,800.00 | $20,794.10 |
| 8 | $19,200.00 | $24,519.05 |
| 9 | $21,600.00 | $28,467.50 |
| 10 | $24,000.00 | $32,652.86 |
Assumptions
- Equal amounts are invested at the start of each period. The assumed return is an effective annual rate applied evenly through the periods: growth is smooth at the assumed rate; no volatility is simulated.
- Price path mode buys amount ÷ price shares each period at the prices you enter. No market data is used or fetched.
- Taxes, fund fees and trading costs are not included. Dollar-cost averaging does not guarantee a gain: when the final price is below the average cost, the ending value is below the amount invested, which price path mode can show.
Worked examples
These results come from the same code as the calculator. They are FedRateCalc arithmetic, not examples printed by a regulator.
| Case | Result |
|---|---|
| $1,000 at the start of each year for 3 years, assuming 10% a year | Invested $3,000.00; balances $1,100.00, $2,310.00, $3,641.00 at the end of years 1, 2 and 3 |
| $100 invested at prices of $10, $20 and $25 | 10 + 5 + 4 = 19 shares for $300.00; average cost $15.79 against a simple average price of $18.33; value at $25: $475.00 |
| $100 invested at prices of $10, $8 and $5 | 10 + 12.5 + 20 = 42.5 shares for $300.00; average cost $7.06; value at $5.00: $212.50, which is $87.50 less than the amount invested |
Interest-bearing alternatives with a stated rate are covered by the I bond calculator and the CD rate calculator.
What the method is, and what it does not do
Investor.gov, the SEC's investor education site, describes dollar-cost averaging in its glossary:
“Dollar-cost averaging means investing your money in equal portions, at regular intervals, regardless of the ups and downs in the market. This investment strategy can help you manage risk by following a consistent pattern of adding new money to your investment over a long period of time. By making regular investments with the same amount of money each time, you will buy more of an investment when its price is low and less of the investment when its price is high.”
The method does not guarantee a gain, and FedRateCalc's own arithmetic shows why: the shares bought at each price are worth the final price times the number of shares. When the final price is below the average cost per share, the ending value is below the amount invested, as in the falling price example above. FINRA's investor education page on the method (dated May 19, 2026) lists limitations:
“While dollar-cost averaging can be a helpful tool in lowering risk, following this strategy can also potentially impact returns. Holding onto your money as cash longer and spreading out your investments gradually has lower risk but often produces lower returns than lump sum investing, especially over longer periods of time. The trade-off is that while dollar-cost averaging may reduce the impact of short-term market swings, you could also miss out on some gains since part of your money stays in cash instead of being invested right away.”
“If you pay commissions or other fees for each transaction, dollar-cost averaging might result in higher fees than lump sum investing due to the greater number of transactions you’ll have, which could erode your returns.”
On projecting performance, FINRA Rule 2210 sets content standards for member firms' communications. Its paragraph (d)(1)(F) says:
“(F) Communications may not predict or project performance, imply that past performance will recur or make any exaggerated or unwarranted claim, opinion or forecast; provided, however, that this paragraph (d)(1)(F) does not prohibit:
- (i) A hypothetical illustration of mathematical principles, provided that it does not predict or project the performance of an investment or investment strategy;
[…]”
The examples on this page are hypothetical arithmetic from the numbers entered; they do not predict or project the performance of any investment.
In price path mode, equal amounts buy more shares when the price is low, so the average cost per share is at or below the simple average of the prices. For the cost basis of shares you later sell, the stock average calculator shows the IRS rules on identifying shares. Gains are taxed under the rules in the capital gains tax calculator.
What the calculator assumes
- Assumed-return mode invests an equal amount at the start of each period. The assumed annual return is an effective annual rate, so each period grows by (1 + annual return)^(1 ÷ periods per year) − 1. Growth is smooth at the assumed rate; no volatility is simulated.
- The years must cover a whole number of payments, up to 100 years. A return below −100% is rejected, and a result too large to show is reported as an error, not as Infinity.
- Price path mode buys amount ÷ price shares for each price you enter (up to 1,200) and values them at the price you give for the end, or at the last purchase price.
- Taxes, fund fees, trading costs and dividends are not included. Results are estimates if your assumptions hold.
Frequently asked questions
What is dollar-cost averaging?
Investor.gov (SEC) says dollar-cost averaging means investing your money in equal portions, at regular intervals, regardless of the ups and downs in the market, so you buy more of an investment when its price is low and less when its price is high. The calculator shows what that routine adds up to under the assumptions you enter.
Does dollar-cost averaging guarantee a profit or protect against loss?
No. This is FedRateCalc arithmetic: when the final price is lower than the average cost per share, the ending value is less than the amount invested. For example, $100 invested at prices of $10, $8 and $5 buys 42.5 shares for $300, which are worth $212.50 at $5. FINRA's investor page "The Benefits and Limitations of Dollar-Cost Averaging" adds that spreading out investments "often produces lower returns than lump sum investing, especially over longer periods of time", and the Investor.gov (SEC) definition of the method does not promise a result either.
How does the assumed-return mode work?
FedRateCalc assumes an equal amount is invested at the start of each period and that the assumed annual return is an effective annual rate, so each period grows by (1 + annual return)^(1 ÷ periods per year) − 1. The result is the balance if that return holds every year, not a forecast. Taxes, fund fees and trading costs are not included.
What does the price path mode show?
You enter a price for each purchase date. The calculator buys amount ÷ price shares each period and reports the average cost per share (total invested ÷ total shares). When prices vary this is lower than the simple average of the prices, which is arithmetic consistent with Investor.gov's description that equal amounts buy more shares when the price is low.
Are these results predictions?
No. FINRA Rule 2210(d)(1)(F) says communications "may not predict or project performance" and does not prohibit "A hypothetical illustration of mathematical principles, provided that it does not predict or project the performance of an investment or investment strategy". The rule governs member firms' communications; FedRateCalc uses only the return or prices you type, and its results are arithmetic, not forecasts.
Does the calculator compare dollar-cost averaging with investing a lump sum?
No. The Investor.gov (SEC) dollar-cost averaging definition describes the method and does not compare it with a lump-sum purchase; FINRA's investor page says spreading out investments "often produces lower returns than lump sum investing, especially over longer periods of time". FedRateCalc does not model a lump sum. The tool reports total invested, ending value and, in price path mode, average cost per share for the schedule you enter.
Related calculators and guides
Sources
Pages were read on November 6, 2026. The Investor.gov page was read from an Internet Archive capture taken on the date shown, because investor.gov refused a plain request; the FINRA pages were read directly.
- Investor.gov (SEC): Dollar Cost Averaging, Internet Archive capture of October 26, 2026
- FINRA: The Benefits and Limitations of Dollar-Cost Averaging
- FINRA: Rule 2210, Communications with the Public
Reviewed November 6, 2026. FedRateCalc is not affiliated with the IRS, the SEC or FINRA; their sites are the official sources, and any later change they publish overrides this site. Results are estimates from the numbers you enter, not financial or tax advice.