Stock Averaging Down Calculator
Estimate your new average cost, total invested amount, and required rebound after averaging down a stock position.
What does this calculator answer?
Averaging down lowers your average cost by buying more shares at a lower price. The important question is not only the new average, but also how much the new purchase must rebound to reach break-even.
Inputs
Results
New average cost
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Total invested
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Rebound to break even
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Before you enter values
- Enter current shares in shares so the estimate uses the same unit throughout.
- Enter current average cost in USD so the estimate uses the same unit throughout.
- Enter additional shares in shares so the estimate uses the same unit throughout.
- Enter additional purchase price in USD so the estimate uses the same unit throughout.
How to read the result
- Start with 'New average cost'. This is the main output for the current assumptions.
- Then compare 'Total invested' so you do not judge the scenario from one number alone.
- Then compare 'Rebound to break even' so you do not judge the scenario from one number alone.
Formula
Rebound to break even = (new average cost - new purchase price) ÷ new purchase price × 100
Example
If you own 20 shares at $60 and buy 20 more at $40, your new average cost is $50. The new purchase price would need to rise about 25% to reach that average.
Common mistakes
- Underestimating the rebound needed after a large decline
- Adding capital without checking position concentration
- Treating a lower average cost as a risk reduction by itself
Important note
Averaging down increases position size. This tool is for scenario math only and does not evaluate the stock or business.
Review and update policy
This page was reviewed on August 6, 2026 for formula wording, default inputs, FAQ coverage, and related calculator links. Investing and AI cost calculators do not pull live market prices or account-specific pricing, so you should enter the latest values yourself.
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