How is the new average price calculated?

It is a weighted average of the two purchases: (existing shares × existing average + new shares × new price) ÷ total shares. If fees are enabled, the fee is added to the cost of the new purchase before dividing, so the average reflects what you actually paid rather than the quoted price. Holding 100 shares at 50,000 and buying 100 more at 40,000 gives an average of 45,000.

Why can't I set my target average below the price I'm buying at?

Because averaging pulls your average toward the new price and can never take it past. Every share you add moves the average closer to what you paid for it, so with enough shares the average approaches the purchase price but never crosses below it. The formula shows this directly: the required quantity is divided by the gap between your target and the purchase price, so as that gap closes the quantity needed heads toward infinity. The tool blocks the impossible target rather than returning a meaningless negative number.

Does lowering my average reduce my loss?

No. This is the single most common misreading of the number. Your unrealised loss is set by what the position is worth against what you paid in total, and buying more adds to both sides. What a lower average changes is the price the stock must reach for you to break even, which is genuinely useful — but it achieves that by putting more money into a position that has already fallen. The loss is not reduced; the amount at risk is increased and the break-even point is moved.

My return percentage improved but the loss is the same. Which one is real?

Both, and the pair is the most useful thing this calculator shows you. Say you hold 100 shares bought at 50,000 and the price is now 40,000: you are down 1,000,000, a return of −20%. Buy 100 more at 40,000 and your average falls to 45,000, your return improves to −11.11%, and your loss is still exactly 1,000,000. The percentage improved because it is measured against a larger amount invested, not because any money came back. The rise needed to break even did genuinely fall, from 25% to 12.5%, and that is the real benefit — bought with 4,000,000 of additional exposure to the same position.

How much does a stock need to rise to get back to even?

More than it fell, and the gap widens fast. Down twenty percent needs a twenty-five percent gain, down thirty needs about forty-three, down fifty needs a hundred, and down seventy needs two hundred and thirty-three. This asymmetry is why the break-even price matters more than the percentage move. Averaging down lowers the required gain, which is the whole appeal, but it does so by committing more capital to the same risk.

Can I use this for coins, funds or anything other than stocks?

Yes. The calculation is a weighted average of quantity and price, so it applies to any divisible holding — cryptocurrency, ETFs, funds, even physical goods bought in batches. Enter fractional quantities if your asset allows them. Nothing in the maths is specific to equities.

Is this investment advice?

No. It is arithmetic. The same numbers come out whether the holding is temporarily out of favour or permanently impaired, so this tool cannot tell you which one you own and does not try. A useful test it also cannot run for you: if you held none of this today, would you buy it at this price? If not, a lower average is not a reason to buy more.

Does this tool upload my data?

No. Everything runs right in your browser, so your data never leaves your device — it even works offline once the page has loaded.

📉 Averaging Down Calculator — Both Directions

Enter what you already hold and what you are thinking of buying, and you get the new average price, your total position, the break-even price, the unrealised profit or loss and your return as a percentage. A before-and-after table sits underneath showing how each of those figures moves, which makes the one fact people most often get wrong impossible to miss. Switch to the second mode and it runs the other way: name the average you want to reach and it tells you how many shares and how much cash that takes. Trading fees can be folded in, and nothing you type is stored or sent anywhere.

Averaging down means buying more of a holding after its price has fallen, which lowers the average price you paid per share. An averaging down calculator works out that new average, and can also run the question backwards to tell you how many additional shares a target average would require.

Position you already hold

Average price

Additional purchase

Price

Target average

Current market price

Current price

Leave blank to use the price you are buying at.

Include trading fee %

Before you average down

This calculator answers an arithmetic question, not an investment one. Lowering your average price does not reduce the money already lost, and it does not make a recovery more likely — it only changes the price at which you break even, while increasing the amount you have at risk in a position that has already moved against you. The maths is identical whether the company is sound or failing, so the number here cannot tell you which one you are holding. Decide whether you would buy this position today at this price if you owned none of it; if the answer is no, a lower average is not a reason to buy more.

Private by design. This tool runs entirely in your browser — nothing you enter is uploaded or stored, and it works offline.

About

The forward calculation is a weighted average and nothing more: add the cost of what you hold to the cost of what you buy, then divide by the total number of shares. The reverse calculation is the one people actually come looking for, and it is the same equation rearranged. If you hold q₁ shares at average p₁ and buy at price p₂, the quantity q₂ needed to reach a target average t is q₁(p₁ − t) ÷ (t − p₂). Reading that fraction tells you something the raw number does not: as your target approaches the price you are buying at, the denominator shrinks toward zero and the required quantity runs away to infinity. Pulling your average all the way down to the current price is not merely expensive, it is arithmetically impossible.

That is why the tool refuses a target below the purchase price rather than returning a negative number. A target average must sit strictly between your current average and the price you are paying. Averaging can only ever drag your average toward the new price, never past it, and a calculator that silently returns a negative share count for an impossible target has answered a question that has no answer.

Fees change the reverse calculation more than people expect. A fee is a percentage added to the price you actually pay, so the effective purchase price rises and the gap between it and your target narrows. Because that gap is the denominator, a fee that looks negligible on a single trade can noticeably increase the quantity needed for an ambitious target. Turning the fee option on uses the effective price throughout rather than adding a cosmetic line at the end.

The part worth sitting with is what a lower average does and does not accomplish. It does not recover money already lost, and it does not make a rebound more likely — the company neither knows nor cares what you paid. What changes is the price at which you break even, and what also changes is the amount of money you have committed to a position that has already moved against you. That combination is why averaging down concentrates risk at exactly the moment your original thesis is being contradicted by the market.

The asymmetry of recovery is worth having in front of you while you decide. A holding down thirty percent needs to rise about forty-three percent to get back to even. Down fifty percent needs a hundred percent gain. Down seventy needs two hundred and thirty-three. Lowering your average reduces the gain required, which is real and useful, but it does so by increasing the capital exposed to whatever caused the fall. The arithmetic here is identical whether you are holding a temporarily unloved business or one in genuine decline, so this number cannot tell you which you own. The question that can is simpler: if you held none of this today, would you buy it at this price? If the answer is no, a lower average is not a reason to buy more — it is a reason the position feels harder to leave.

How to use

Enter the shares you already hold and the average price you paid for them. If you have bought in several times, use the average your broker shows, not the price of your first purchase.
In New average mode, enter how many more shares you plan to buy and at what price. The result is your new average, total cost, break-even and current profit or loss.
In Reach a target mode, enter the buying price and the average you want to end up with. The tool returns the quantity and the cash that target requires.
Enter the current market price if it differs from the price you are buying at. Leave it blank and the purchase price is used, which is right for a market order but wrong if you have a limit order sitting below the market.
Tick the fee option and enter your broker's commission rate if you want the effective purchase price used throughout rather than the quoted price.
Read the break-even line, not just the new average. It is the same number, but framed as the price the stock has to reach before you have lost nothing.
Read the before-and-after table last. The loss in money is the row that does not move; the return percentage and the rise needed to break even are the rows that do.

FAQ

How is the new average price calculated?: It is a weighted average of the two purchases: (existing shares × existing average + new shares × new price) ÷ total shares. If fees are enabled, the fee is added to the cost of the new purchase before dividing, so the average reflects what you actually paid rather than the quoted price. Holding 100 shares at 50,000 and buying 100 more at 40,000 gives an average of 45,000.
Why can't I set my target average below the price I'm buying at?: Because averaging pulls your average toward the new price and can never take it past. Every share you add moves the average closer to what you paid for it, so with enough shares the average approaches the purchase price but never crosses below it. The formula shows this directly: the required quantity is divided by the gap between your target and the purchase price, so as that gap closes the quantity needed heads toward infinity. The tool blocks the impossible target rather than returning a meaningless negative number.
Does lowering my average reduce my loss?: No. This is the single most common misreading of the number. Your unrealised loss is set by what the position is worth against what you paid in total, and buying more adds to both sides. What a lower average changes is the price the stock must reach for you to break even, which is genuinely useful — but it achieves that by putting more money into a position that has already fallen. The loss is not reduced; the amount at risk is increased and the break-even point is moved.
My return percentage improved but the loss is the same. Which one is real?: Both, and the pair is the most useful thing this calculator shows you. Say you hold 100 shares bought at 50,000 and the price is now 40,000: you are down 1,000,000, a return of −20%. Buy 100 more at 40,000 and your average falls to 45,000, your return improves to −11.11%, and your loss is still exactly 1,000,000. The percentage improved because it is measured against a larger amount invested, not because any money came back. The rise needed to break even did genuinely fall, from 25% to 12.5%, and that is the real benefit — bought with 4,000,000 of additional exposure to the same position.
How much does a stock need to rise to get back to even?: More than it fell, and the gap widens fast. Down twenty percent needs a twenty-five percent gain, down thirty needs about forty-three, down fifty needs a hundred, and down seventy needs two hundred and thirty-three. This asymmetry is why the break-even price matters more than the percentage move. Averaging down lowers the required gain, which is the whole appeal, but it does so by committing more capital to the same risk.
Can I use this for coins, funds or anything other than stocks?: Yes. The calculation is a weighted average of quantity and price, so it applies to any divisible holding — cryptocurrency, ETFs, funds, even physical goods bought in batches. Enter fractional quantities if your asset allows them. Nothing in the maths is specific to equities.
Is this investment advice?: No. It is arithmetic. The same numbers come out whether the holding is temporarily out of favour or permanently impaired, so this tool cannot tell you which one you own and does not try. A useful test it also cannot run for you: if you held none of this today, would you buy it at this price? If not, a lower average is not a reason to buy more.
Does this tool upload my data?: No. Everything runs right in your browser, so your data never leaves your device — it even works offline once the page has loaded.