Formulas
Percentages are converted to decimals for calculation. Monetary inputs use one currency throughout; selecting a currency changes formatting and does not perform an exchange-rate conversion.
| Tool | Calculation |
|---|---|
| Loss recovery | Loss ÷ (1 − loss), using decimal loss |
| Position size | Position value ÷ portfolio value |
| Portfolio loss | Portfolio value × allocation × position loss |
| Diversification illustration | Loss in one holding ÷ number of equal-weight holdings |
For example: a 40% loss requires 0.40 ÷ 0.60 = 0.6667, or approximately 66.67%, to recover. A position worth $10,000 in a $100,000 portfolio is 10%. If that position falls 40%, the portfolio loses $4,000, or 4%, when other holdings stay flat.
Assumptions and boundaries
Calculators model unleveraged positions. Total portfolio value includes the position being measured. There are no deposits, withdrawals, dividends, fees, taxes, inflation adjustments, or currency changes. The portfolio loss tool assumes all other holdings stay unchanged. The diversification illustration assumes equal weights, exactly one holding falls, and all the others stay flat. It does not model correlations or estimate overall portfolio risk.
A selected loss is a scenario, not a probability estimate or a loss limit. A 100% loss leaves zero value to compound. Negative losses, borrowed positions, and allocations above 100% are outside these tools.
Rounding and inputs
Percentage results are displayed to two decimal places on the dedicated calculators; money is displayed to two decimal places. Calculations use the entered values before display rounding. Portfolio and starting amounts must be greater than zero and no more than one trillion. Position amounts may be zero and cannot exceed the portfolio total.
How the pages are made
investor.wtf publishes the calculators and explanations with AI assistance. A shared template creates the pages from a defined set of tools and worked examples. The numerical outputs use explicit formulas, not AI-generated forecasts.
The thesis template records the visitor’s own reasoning. Its completion count measures answered questions and is not an investment quality score.
Your inputs
These tools calculate in your browser. They do not submit calculator amounts or thesis answers to a server, and they do not save your notes across reloads. Copy your memo to keep it. Ordinary website hosting may receive request information needed to serve the page.
Further reading
FINRA: Concentrate on Concentration Risk explains how overlapping or large exposures can amplify losses. Investor.gov: Diversify Your Investments explains diversification and its limitations.
This site provides educational tools and reflection prompts. It does not provide personalized investment advice or security recommendations.