CAPM Calculator guide
CAPM links expected return to systematic market risk measured by beta. The market-risk premium is multiplied by beta and added to the risk-free rate.
The model is a simplifying framework; estimates depend on benchmark, horizon, and input assumptions.
How to use the CAPM calculator
- Enter current amounts: Use current, documented values from the same relevant period.
- Enter assumptions: Use realistic rates, percentages, periods, and costs where applicable.
- Review the full result: Review the primary estimate together with its supporting measures.
- Stress-test risk: Model less favorable timing, value, cost, or rate assumptions.
Formula and variables
The estimate applies the entered values and assumptions to the stated formula.
Required return = risk-free rate + beta × (market return − risk-free rate)- Inputs — Entered values
- The amounts, percentages, or periods supplied to the calculator.
- Result — Calculated output
- The estimate produced by applying the formula to the entered values.
Worked example: CAPM calculator
A user enters a representative set of values and assumptions.
- Key inputs
- Amounts, percentages, periods, and costs
- Apply the stated formula.
- Include all relevant entered values and constraints.
- Compare the result with an alternative scenario.
Result: CAPM required return, risk contribution, and observed alpha.
Use the estimate as a planning input and verify important decisions with current records or qualified guidance.
Understanding your results
Primary estimate
CAPM required return, risk contribution, and observed alpha.
Risk measures
Use supporting payment, leverage, cost, and cash figures together.
Assumptions
- Entered rates and costs remain constant.
- Payments and cash flows occur on schedule.
Limitations
- Taxes, legal terms, accounting treatment, and transaction-specific costs may differ.
- Future values, timing, and rates are uncertain.
Common mistakes
- Reviewing only the headline result.
- Ignoring relevant costs, timing, or supporting measures.
- Using optimistic timing or value assumptions.
- Treating an estimate as a guaranteed outcome.
Practical use cases
Compare scenarios consistently
Change one assumption at a time or enter each alternative using the same basis.
Plan cash requirements
Estimate funds needed before committing.
Planning and decision guide
Stress-test the assumptions
Match risk-free maturity and market-return horizon to the analysis.
Review the important risks
Treat beta and expected market return as uncertain estimates.
Verify the source values
Use CAPM alongside valuation, fundamentals, and scenario analysis.
Frequently asked questions
What does beta mean in CAPM?
Estimated sensitivity to broad market returns.
Can beta be negative?
Yes, though stable negative estimates are uncommon.
What is alpha here?
Observed or forecast return minus the CAPM required return.
Does CAPM predict actual return?
No. It estimates required return under model assumptions.
Sources and review
- Introduction to investing — U.S. Securities and Exchange Commission. Accessed 2026-07-10.
Reviewed 2026-07-10.