DCA & Average Down Calculator
Two modes: lower your average cost across multiple buys, or plan a recurring DCA strategy with a starting capital, regular contribution and expected return.
Inputs
Result
Inputs
Result
How to use the Average Down Calculator
Enter your existing position as the first row (units and the price you originally paid), then add each subsequent buy with the "+ Add Purchase" button — up to five extra purchases. The calculator returns your new average cost, total units, total dollars invested, and the break-even price after fees. Once you have closed a position, double-check the realised return with the ROI Calculator.
The math behind averaging down
Average Price = Σ (Units × Price) ÷ Σ Units. Because the average is weighted by units, adding a large buy at a much lower price pulls your basis down hard — but it also concentrates more capital in a single name. The "% vs. First Buy" output tells you exactly how far the average shifted from the price you originally paid; if it shifted further than your stop tolerance, you may be averaging into a losing thesis rather than a temporary dip.
Dollar Cost Averaging explained
The DCA Planner models the standard SIP future-value formula: it grows your starting capital at the expected periodic rate and adds each recurring contribution into the same compounding stream. For a longer horizon view that ignores periodic timing and just compares total contributions to a target growth rate, see the Compound Interest Calculator — the two tools share the same maths but expose different inputs.
DCA vs. Lump Sum Investing
For investors who already hold the cash, lump-sum tends to beat DCA over long horizons because more money compounds for longer. For investors with a regular paycheck, the real comparison is DCA vs. leaving the money in cash — in which case DCA almost always wins, both empirically and behaviourally (it's easier to keep doing).
Frequently Asked Questions
What is Dollar Cost Averaging?
Dollar Cost Averaging (DCA) is the strategy of investing a fixed amount on a regular schedule — weekly, monthly or quarterly — regardless of the asset's price. Because the same dollar amount buys more units when the price is low and fewer when it is high, your average cost per unit tends to sit below the simple arithmetic mean of the prices you paid. DCA is a way to take emotion and market-timing out of the process, not a guarantee of better returns.
How do I calculate my average purchase price?
Add up the total dollar amount you have invested across every purchase, then divide by the total number of units (or shares) you now hold. Average Price = Σ (Units × Price) ÷ Σ Units. This is a weighted average — a large buy at a low price pulls the average down more than a small buy. The Average Down tab on this page applies the same formula across up to six purchases.
What is the break-even price?
Your break-even price is the price at which a sale would recover your full cost basis including trading fees — selling above it locks in a profit, selling below it locks in a loss. The formula is Average Price × (1 + Fees ÷ 100). The Average Down tab shows this value so you can see exactly how much the asset needs to recover before you are whole again.
DCA vs. Lump Sum: which performs better?
Empirically, lump-sum investing outperforms DCA about two-thirds of the time in long-term studies, because markets trend up most years and money put to work earlier compounds longer. DCA wins in down or sideways markets and is psychologically easier — you avoid the regret of investing everything right before a crash. For most retail investors with regular paychecks, the choice is really DCA vs. cash on the sidelines, in which case DCA almost always wins.
Log every DCA buy in the Trading Journal
Track entries, exits and your real per-asset average cost over time — alongside R-multiples and an equity curve.