Stocks
Stock Average Down Calculator
See your new average after buying more at a lower price.
How the calculation works
Starting from an existing average cost and share count, the calculator adds a new purchase at a (typically) lower price. New average = total cost of old plus new lots ÷ combined shares. Total risk exposure rises with the added shares even as average price falls.
Formula & example
New average = (existing shares × avg + buy shares × buy price) ÷ total shares
100 @ $50 plus 100 @ $40 → new average $45 on 200 shares.
Why use this calculator
Averaging down can look attractive on paper while quietly concentrating risk. Seeing the new average and total shares side by side forces the size decision into the open.
When to use it
Use only when you are actively considering an add after a decline — to see the new basis and total size before clicking buy.
Tips for accurate results
- Averaging down is not always good risk management.
- Check position size vs account risk.
FAQ
Should I average down?
Only if the thesis still holds and the larger size fits your risk plan. This calculator does not advise whether to add.
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