Stock Average Calculator — Calculate Your New Average Price
Use our stock average calculator (also called a stock average down calculator or stocks price average calculator) to quickly find your updated cost basis after additional buys.
Why use a stock average calculator?
When you buy the same stock at different prices, your overall cost per share becomes a weighted average. A stock average calculator removes manual math and shows the exact new average price, total shares you hold, and total cost. This is essential when you plan to average down during dips.
How the calculation works
- Multiply quantity × price for each purchase to get the cost per purchase.
- Sum all quantities to get total shares.
- Sum all costs to get total cost.
- Divide total cost by total shares to get the average stock price.
Example: Buying 100 shares at 120 and 50 shares at 100 results in a weighted average price of (100×120 + 50×100) ÷ 150 = 113.33.
Practical tips for averaging down
- Only average down if the company's fundamentals remain intact.
- Use a fixed budget rather than chasing falling prices endlessly.
- Diversify — avoid concentrating too much in a single position even when prices seem attractive.
Try the calculator
Ready to compute? Use the interactive Stock Average Calculator above to enter multiple buys and see live results.
Frequently Asked Questions
What is a stock average down calculator?
A tool to calculate how additional share purchases at different prices influence your overall average price.
How many purchases can I include?
Most calculators allow multiple entries — our tool supports adding several rows so you can model many buys.
Does the calculator show profit/loss?
You can enter the current market price in some calculators to see unrealized profit or loss based on the new average price.