Stock average calculator: enter each purchase of a share — quantity and price — and the page works out your average buy price, total shares and total amount invested.
Use it to see how a new purchase at a lower or higher price changes your share average price. It works for NSE and BSE shares in rupees and for US stocks in dollars.
The whole math happens in your browser. No number ever leaves it.
Purchase rows
| # | Quantity | Price per share | |
|---|---|---|---|
| 1 | |||
| 2 |
Row: 2 / 10
Result
- Average buy price
- —
- Total shares
- —
- Total amount invested
- —
- Rows counted
- —
- Currency
- —
Quick Answers
- How do you work out the average price of a stock?
- Average = total amount paid ÷ total shares. Say 100 shares at 250, then 50 more at 220. Total paid is 25,000 + 11,000. Divide that by 150 shares. The average is 240.
- Does this calculator include brokerage and taxes?
- No. It divides the 2 raw figures you enter — amount and share count. For the cost side, the brokerage calculator lists those charges on its own.
How The Average Price Is Worked Out
Total cost = Σ (shares × price). Total shares = Σ shares. Average price = total cost ÷ total shares. Each purchase carries its own share count as weight.
A Worked Example
The numbers below are an illustration of the method only. They are not taken from any stock and they are not a suggestion to trade.
| # | Shares | Price | Cost |
|---|---|---|---|
| 1 | 50 | ₹1,200.00 | ₹60,000.00 |
| 2 | 30 | ₹1,100.00 | ₹33,000.00 |
| 3 | 20 | ₹1,050.00 | ₹21,000.00 |
| Total | 100 | — | ₹1,14,000.00 |
Average price = ₹1,14,000.00 ÷ 100 shares = ₹1,140.00.
A plain average of the three prices would read ₹1,116.67 — lower than the weighted ₹1,140.00, because it gives every purchase the same weight whatever its share count.
Averaging Down: Adding One More Purchase at a Lower Price
Add a fourth row of 100 shares at ₹1,000.00. The total cost becomes ₹2,14,000.00 for 200 shares, and the average price becomes ₹1,070.00.
The fourth row moves the average by ₹70.00 because it carries as many shares as the first three rows together. A small row at the same price would move it far less — the weight of each row is its share count.
This number is built only from the rows you enter. It includes no brokerage, no taxes and no other charge. It is not investment advice of any kind.
Related pages
Frequently Asked Questions
How is the average price worked out?
Average price = total cost ÷ total shares. Total cost adds up shares × price, row by row. Total shares adds up the share count of all rows.
Why not take a plain average of two prices?
(price1 + price2) ÷ 2 is correct only when the share count is the same both times. If share counts differ, each price carries its own weight. Say 10 shares at ₹100 and 90 shares at ₹200 — that gives a weighted average of ₹190. The plain average would read ₹150 instead.
What does averaging down mean?
Averaging down is buying more of a share you already hold at a lower price than before, which pulls the average buy price down. This page only shows the arithmetic of it; whether to buy more is your own decision.
Can I use it for US stocks in dollars?
Yes. Choose US dollar as the currency. The math is the same; only the grouping of digits and the labels change. Fractional quantities are accepted.
How many rows can be entered?
At most 10. Each row is its own purchase, with its own share count and its own price.
What happens if a row is left empty?
A blank row does not enter the math at all. A row with shares but no price is an error. The page marks that row and leaves its result empty.
Are brokerage and charges included?
No. This is only the average of shares and price. To add charges, use the brokerage calculator.
Do the numbers I enter go to a server?
No. The whole math happens in your browser. No number goes to any server, and nothing is saved.