Crypto DCA calculator with fees
Model recurring crypto purchases with trading fees, average cost, and a 364-day real Bitcoin price backtest cross-checked across two exchanges.
Enter a starting price, an ending price, and a fee. The calculator walks a straight path between them and shows what a fixed schedule of buys would accumulate. It is a scenario tool, not a forecast. Below it, a backtest replays the same math against 364 real daily Bitcoin prices.
No market feed is used. Every price, rate, fee, and balance comes from the values you enter.
Your inputs
Inputs and results stay in this browser. Values are capped to keep calculations finite and responsive.
Calculated result
- Total invested
- $6,000.00
- Units accumulated
- 0.09391777
- Average cost
- $63,885.67
- Ending value
- $7,513.42
- Gain or loss
- $1,513.42
- Purchases
- 24
Cash invested divided by units received
The calculation
What dollar cost averaging changes
Dollar cost averaging divides one allocation into repeated purchases. When prices fall, a fixed contribution buys more units. When prices rise, it buys fewer. The result is a weighted average cost determined by the complete path, not simply the midpoint between the first and last price.
This model spaces prices evenly along the path you enter. Real markets do not move in a straight line, so two histories with the same endpoints can produce different accumulated units. Use several scenarios rather than treating one output as a prediction.
How fees compound across purchases
A percentage fee reduces the amount converted into the asset on every purchase. Small fees can become visible across dozens of contributions because each charge also removes units that would otherwise participate in later price changes.
The total invested figure includes the full cash contribution. Units are calculated from the contribution after the entered fee. Spread, slippage, network charges, taxes, and subscription costs are outside this model.
When to compare a lump sum
A lump sum gets the full allocation exposed immediately. A recurring plan delays part of that exposure. In a steadily rising scenario, the earlier lump sum generally accumulates more units. In a falling scenario, later recurring purchases generally lower the average cost.
That comparison is about timing risk, not a universal winner. Match the scenario to cash availability, the maximum loss you can tolerate, and whether the plan can be followed during a drawdown.
$250 invested 24 times
With 24 contributions of $250, the cash invested is $6,000. If the modeled price rises from $50,000 to $80,000 and each purchase costs 0.25%, the calculator adds the units bought at all 24 prices, then values that combined balance at $80,000. Change the ending price below the starting price to test how buying more units later affects average cost.
Questions and answers
Does this DCA calculator predict future crypto prices?
No. The entered start and end prices define a straight scenario path. They are assumptions supplied by you, not a forecast from Early Thunder.
Are fees included in the average cost?
Yes. Total cash contributions are divided by the units received after the entered purchase fee, so the average cost reflects that fee.
Why can two DCA plans with the same start and end price differ?
The prices between the endpoints determine how many units each contribution buys. This model uses evenly spaced prices, while a real price history can follow a different path.
Where does the backtest data come from?
The backtest section below uses 364 published daily Bitcoin prices from CoinGecko, cross-checked against Kraken at a 1% tolerance, fetched on the date stated in the data disclosure. It is a historical record, not a forecast.
Method and sources
The formulas run only on your inputs. These references support the definitions and risk notes on this page. They do not supply prices or predict a result.
- Investor.gov dollar-cost averaging glossary
Defines equal purchases at regular intervals and explains why a fixed amount buys more units at lower prices.
- SEC bulletin on investment fees
Explains that transaction fees reduce the money left in an investment and should be checked against account records.
Related calculators
Research and risk disclosure
This calculator is an educational planning model, not investment, tax, or trading advice. It does not predict returns or execution. Crypto assets can lose their entire value. Confirm actual fills, fee schedules, funding, taxes, and account balances with the relevant provider before acting.
Built and checked by Michael Lip. Method assumptions are stated on this page so the result can be reproduced independently.
Backtest of $100 every week for a year
The calculator above runs on a straight line between two prices. Real markets do not move that way. So below, the same math runs against 364 dated daily Bitcoin prices, $100 every week at a 0.25% fee.
Cash invested
$5,200.00
52 weekly purchases, Sep 19, 2025 to Sep 18, 2026
Average cost
$77,931.40
against a final price of $76,325.39
Ending value
$5,092.84
0.06672535 units, -2.06% ROI
Fee drag on the same schedule
| Fee | Units | Ending value | Cost of fees | ROI |
|---|---|---|---|---|
| 0% | 0.06689258 | $5,105.60 | baseline | -1.82% |
| 0.1% | 0.06682569 | $5,100.50 | $5.11 | -1.91% |
| 0.25% | 0.06672535 | $5,092.84 | $12.76 | -2.06% |
| 0.5% | 0.06655812 | $5,080.07 | $25.53 | -2.31% |
| 1% | 0.06622365 | $5,054.55 | $51.06 | -2.80% |
DCA versus lump sum on the same cash
Over the same year, the weekly schedule ended up $1,713.96 more than investing all $5,200.00 at once on September 19, 2025. The weekly buys averaged $77,931.40 per coin, below the $117,169.12 a single entry paid on day one, so spreading the purchases caught dips the lump sum never saw.
Data disclosure
- Published readings: 364 of 365 days, September 19, 2025 through September 18, 2026.
- Prices pulled from CoinGecko and cross-checked against Kraken, with a 1% tolerance between the two sources.
- Readings for 2026-02-23 were dropped: cross-check disagreement 3.71% between CoinGecko ($65192.19) and Kraken ($67612.10).