DCA Calculator

What Is the DCA Calculator?

The DCA Calculator is a free backtesting tool for dollar-cost averaging. Instead of guessing how a regular investment plan would have turned out, you enter an amount, a frequency and a date range, and the calculator replays every scheduled purchase against real daily closing prices. It then reports what the position would be worth today, how much profit or loss it would show, which months were the strongest and weakest, and how the same money would have performed if it had all been invested on day one. It covers 20 popular assets across crypto, stocks, exchange traded funds and gold, so one page handles both a Bitcoin savings plan and an S&P 500 contribution schedule.

Why Use It and Who It Is For

Regular investing works because it removes the pressure of timing the market, but it is hard to picture the outcome in your head. This tool turns that picture into numbers you can check.

• Long term savers who put money into an index fund every month and want to see what that habit historically produced.
• Crypto accumulators testing weekly or monthly Bitcoin or Ethereum buying against a lump sum entry.
• Students of investing comparing strategies side by side instead of relying on rules of thumb.
• Financial writers and educators who need concrete historical examples for an article or a class.
• Anyone hesitating to start who wants evidence of what consistency did over five or more years.
• People paid in another currency who want results in INR, BRL, NGN or any of the 36 supported currencies.

How This Tool Works

The simulation is a straightforward replay of a savings plan. First the calculator loads daily closing prices for your asset over your date range. Then it groups those days into buckets: one purchase per day for daily frequency, one per week for weekly, and one per month for monthly. The purchase price is the first price available inside that bucket, which is how a real order behaves when it lands on the first trading day of the week or month.

For each purchase the calculator applies two formulas:

Units bought = investment amount / price on that day
Total units = sum of units bought across all purchases

From there: current value = total units x price of the last purchase, profit = current value - total invested, and ROI = profit / total invested x 100. Average buy price is simply total invested divided by total units. The lump sum comparison takes the very same total amount, buys once at the first purchase price, and holds to the end of the range, so both strategies are measured over exactly the same days and the same final price.

Best and worst months are calculated from the asset price itself: for every month in your range the change from that month first close to its last close is measured as a percentage, and the highest and lowest of those are reported. History comes from Binance daily candles for crypto with Coinbase as a fallback, and from Yahoo Finance for stocks, ETFs and gold with Stooq as a fallback. Price history starts on 1 January 2017 and is refreshed once a day, so repeat runs are fast and consistent.

Key Features

• 20 assets: 8 cryptocurrencies, 7 stocks, 4 index ETFs and gold.
• Real historical daily prices from 2017 to the latest available trading day.
• Daily, weekly or monthly contribution schedules.
• Full purchase simulation with date, price, amount, units bought, total units and total invested per row.
• Summary cards for total invested, current value, profit and loss, ROI, average buy price, purchase count and units owned.
• DCA versus lump sum panel with the difference and a badge naming the winner.
• Portfolio value over time chart comparing your value against the money invested.
• Best month and worst month with their percentage change.
• A plain language explanation paragraph written from your exact numbers.
• 36 display currencies converted with live exchange rates.
• Works as soon as the page loads - the default run uses a five year window ending today.

How to Use This Tool

1. Open the Asset dropdown and choose one of the 20 instruments. The hint under the field shows the name, symbol and type.
2. Enter your Investment Amount per purchase. The field defaults to 100 and accepts between 1 and 1,000,000.
3. Pick a display currency next to the amount field if you do not want USD.
4. Click Daily, Weekly or Monthly to set the contribution frequency. Monthly is selected by default.
5. Set the Start Date and End Date. The page pre-fills a five year window ending today, and neither date may be later than today.
6. Click Calculate. Results appear in the right hand panel.
7. Read the summary cards, then scroll for the DCA versus lump sum comparison, the value chart and the monthly breakdown table.
8. Read the written explanation under the table - it restates your numbers in one sentence so you can share the result.

Limits and Rules

The amount per purchase must be between 1 and 1,000,000. The start date must fall on or after 1 January 2017 and on or before today, and the end date must be on or after the start date and no later than today. A range outside the available price history is rejected with a clear message, as is a range in which no purchase is possible. The calculate endpoint allows 60 requests per minute, which is far beyond interactive use. Purchases only happen on days where the source actually published a price, so weekends and market holidays naturally produce fewer rows for stocks and ETFs. Results depend on cached history that is refreshed once a day, and everything shown is historical illustration only - this is not financial advice and past performance never guarantees future results.

When to Use It and When Not To

Use it to decide between starting a regular plan and waiting for a dip, to compare daily against weekly against monthly contributions, to see whether a strategy would have survived a rough year, and to explain the idea of averaging to someone who is new to investing. It is also useful for setting realistic expectations before you commit money you will need soon.

Do not use it to predict future returns, to pick a single stock on the strength of a backtest, or to plan around a date range shorter than a few months where one bad week can dominate the result. It also cannot model fees, taxes, dividends reinvested automatically, or partial fills, because it works from closing prices only. If you need those details, treat the output as a first estimate and do the fine tuning elsewhere.

Frequently Asked Questions