Dollar-cost averaging calculator
Model a recurring investment in Bitcoin, S&P 500 or gold. Choose a contribution amount, frequency and date range to see historical units, total invested, average cost and current value.
Calculate for freeStart with a historical scenario
These examples only fill the calculator. Keep the contribution amount, frequency, currency and date range visible before comparing results.
🔒 = Locked assets were not listed on the selected date.
Investment Details
Currency
Investment Frequency
This date stops contributions, not valuation. Accumulated units are valued at the latest available price and exchange rate; this is not the portfolio value on the last contribution date.
Fixed historical example: 2–4 January 2024. This is not today’s value or a return forecast. Daily closes are shown below; arithmetic uses the unrounded observations.
| Observation date | Close (USD) | Contribution (USD) | Calculated units |
|---|---|---|---|
| 2024-01-02 | 44,957.9688 | 100.00 | 0.00222430 |
| 2024-01-03 | 42,848.1758 | 100.00 | 0.00233382 |
| 2024-01-04 | 44,179.9219 | 100.00 | 0.00226347 |
Σ (100 ÷ close) = 0.00682159; 300.00 ÷ 0.00682159 = 43,978.00
0.00682159 × 44,179.9219 = 301.38 USD
Three equal daily contributions, including the final valuation day. Units = sum of each contribution ÷ its closing price; average cost = total contributions ÷ total units.
No currency conversion, tax, fees or inflation adjustment. Different providers and closing times may produce different results.
Source data (Yahoo Finance) · Retrieved: 2026-09-14
Open the calculatorIt calculates the units bought at each valid historical contribution date, adds those units together and values the total at the latest available price. It does not apply one average annual return to the entire budget.
Yes. Select S&P 500, GBP and a monthly contribution to test a historical recurring-investment scenario. Tax, broker fees, fund fees and spreads are not included.
Yes. Choose Bitcoin or gold, then set the contribution amount, frequency and dates. Results are historical simulations and do not predict future returns.
No. Contribution frequency changes the dates and transaction assumptions, but it does not guarantee a better return. Compare scenarios with the same total budget and time period.
The calculator estimates units purchasable at the historical price and values them at the latest valid market price. It is a historical simulation, not a forecast.
Tax, broker commission, bid-ask spread and custody costs vary by user and are excluded by default.
Start date can materially change the outcome. Test multiple dates, compare DCA and review inflation separately.
HowMuch? · vibecodingstudios@gmail.com
Use the DCA calculator to model a fixed contribution made daily, weekly or monthly over a historical date range. Rather than applying an annual average return to the entire budget, the tool calculates the units purchased at each valid observation and adds them together before valuing the portfolio.
That makes the total contribution, frequency, asset, currency and end date essential assumptions. A plan funded from monthly income is also different from holding a lump sum today and deliberately delaying part of it; the latter introduces a cash opportunity-cost decision.
Average cost is total amount invested divided by total units accumulated. It is not the simple average of all quoted prices. Lower prices buy more units for the same contribution, while fees or spread can reduce units in a real account.
More frequent purchases can spread entry dates more finely but can also increase fixed transaction costs. Hold the total budget and time window constant when comparing frequencies; otherwise a higher ending value may simply reflect investing more money.
DCA distributes entry dates but cannot make a weak asset suitable, prevent loss or eliminate currency, tax, custody and liquidity risk. Review the worst historical period as carefully as the best return before making a personal decision.
