Stock Average Calculator

What is a stock average calculator?

When you buy the same share at different prices, your cost per share is the weighted average of all your purchases: total amount paid divided by total shares held. That average decides your profit or loss, and how far the price must move for you to break even.

This stock average calculator combines up to three purchases, shows your average buy price, total investment, current value and unrealised profit or loss, the move needed to break even, and how many shares you would need to buy at today’s price to bring your average down to a target.

How this calculator works

When you buy the same share at different prices, your cost per share is the weighted average: the total amount paid divided by the total number of shares. Bigger purchases pull the average further towards their price.

Enter today’s market price to see your unrealised profit or loss. Add a target average and the calculator works out how many shares you would need to buy at today’s price to bring your average to that level — the question behind “averaging down”.

It works equally for mutual fund units, ETFs, gold or crypto — anything bought in lots at different prices.

Formula

Average price = (q₁ × p₁ + q₂ × p₂ + …) ÷ (q₁ + q₂ + …)

Shares to buy at price c to reach target T:
n = Q × (A − T) ÷ (T − c)      Q = shares held, A = current average

Worked example

1. 50 shares at ₹1,250 and 30 more at ₹980.
2. Average = (62,500 + 29,400) ÷ 80 = ₹1,148.75.
3. At a market price of ₹1,020, bringing the average to ₹1,100 needs 80 × 48.75 ÷ 80 ≈ 49 more shares.

Worked example: averaging down

You bought 50 shares at ₹1,250 and later 30 more at ₹980. You now hold 80 shares for ₹91,900, an average of ₹1,148.75. At today’s price of ₹1,020 the holding is worth ₹81,600 — an unrealised loss of ₹10,300 (11.2%). The share has to rise about 12.6% from here for you to break even.

Buying more at a lower price reduced the average from ₹1,250, but it also increased the amount at risk in a share that was falling.

When averaging down makes sense — and when it does not

• It can make sense when the fall is due to market-wide weakness and the company’s business and outlook are unchanged.
• It is dangerous when the price is falling because the business has deteriorated — a lower average does not help if the share keeps falling.
• Set a limit on how much of your portfolio any single stock can become before you add more.
• For diversified mutual funds, regular SIPs achieve the same averaging automatically and with far less concentration risk.

Assumptions & important notes

Frequently asked questions