Use exact daily UTC closing prices

The CSV must use the date,price header and real UTC dates. This model declares daily close as its price convention; you must verify the source uses it and quotes prices in USD. Each purchase date and the final valuation date need an exact price. Missing dates cause an error. The calculator never interpolates, skips a buy or substitutes a chart sparkline.

The first purchase occurs on the start date. Weekly purchases advance seven UTC days. Monthly purchases retain the original day: January 31 clamps to February 28 in 2025 and returns to March 31. A purchase on the final date happens before that day's valuation.

Budgets include purchase fees

Tokens per buy = (purchase budget − budget × percentage fee − fixed fee) / daily price
Final value = total purchased tokens × final daily price
Simple return = (final value − total contributed budget) / total contributed budget

The synthetic example uses three monthly $100 budgets at prices 100, 50 and 100. A 1% fee on each budget leaves 3.96 tokens. At the final price of 100, they are worth $396 against a $300 total budget, a $96 gain or 32% simple return. These are invented example prices, clearly labeled synthetic rather than historical market data.

The equal-budget comparison assumes early cash availability

The benchmark invests the same $300 on the start date, charging one fixed fee rather than a fee per scheduled purchase. With the example's 1% fee, it buys 2.97 tokens and ends at $297. That comparison assumes the full budget existed at the start. Cash waiting for DCA purchases earns zero in the model. Neither return is annualized or time-weighted.

A price file has limits

A file can omit failed or delisted assets, use a different venue, or reflect a source's revised data. The website does not verify its provenance. Fees on a final sale, spread, slippage, taxes, staking and inflation are excluded. Browser-selected files stay in this browser; without JavaScript, pasted CSV is sent transiently to PHP. Saved scenarios retain settings and a normalized digest, requiring the file again.

Use the DCA calculator to inspect the scheduled rows and benchmark assumptions. The average entry calculator answers a different question using purchases you already know.