Calculate the portfolio impact
Multiply the position weight by the loss on that position, with both expressed as decimals. Multiply by the portfolio value to get the money lost.
For a $100,000 portfolio with a 10% position: $100,000 × 0.10 = $10,000 invested. A 40% loss on that position costs $10,000 × 0.40 = $4,000. The remaining portfolio is $96,000 if everything else stays flat.
Same asset loss, different portfolio impact
This comparison holds the loss on the position at 40% and changes only its share of a hypothetical $100,000 portfolio.
| Position weight | Loss on position | Portfolio loss | Money lost |
|---|---|---|---|
| 5% | 40% | 2% | $2,000 |
| 10% | 40% | 4% | $4,000 |
| 25% | 40% | 10% | $10,000 |
| 50% | 40% | 20% | $20,000 |
What this scenario leaves out
This is a single-position calculation for an unleveraged portfolio. It assumes no deposits, withdrawals, taxes, fees, or currency changes. It also assumes every other holding stays unchanged.
In practice, several holdings can fall together. The scenario you enter is not a maximum possible loss. Diversification can help spread risk, but cannot guarantee protection against losses. Read Investor.gov on diversification.
Frequently asked questions
What if this position loses 100%?
The portfolio loses the full amount allocated to that position, assuming all other holdings stay flat. A 10% allocation going to zero reduces the whole portfolio by 10%.
Can this predict my future portfolio value?
No. You choose a hypothetical loss and the tool applies arithmetic. It does not estimate probabilities, expected returns, or future prices.
Can I model several positions?
This page models one position. Losses across multiple holdings must be combined using consistent starting portfolio weights, and a complete analysis may need to account for correlated changes.
Published by investor.wtf. Read the formulas, assumptions, and how these pages are made.