CAPM Calculator - Beta-Based Return

A CAPM calculator estimates the expected return for an asset using the Capital Asset Pricing Model. Use it when you need a beta-based return hurdle for a stock, a cost of equity input for valuation, a discount-rate assumption for a model, or a quick check on whether a forecast return is above or below the return CAPM would imply.

• • Estimate cost of equity: Enter an equity beta, a risk-free rate, and an expected market return to get a CAPM-style cost of equity for valuation work.
• • Review a stock forecast: Compare an analyst forecast or required return with the CAPM result to see the implied alpha.
• • Document rate assumptions: Keep beta, market risk premium, and risk-free-rate assumptions visible instead of burying them in a spreadsheet cell.
• • Stress-test market expectations: Change the expected market return or beta to see how sensitive the required return is to the market premium.

Use the CAPM calculator as a focused worksheet, not as a full valuation model. It does not forecast cash flows, price a stock, or decide whether a security is attractive. It turns four assumptions into a return estimate: beta, risk-free rate, expected market return, and an optional forecast or required return.

CAPM is most useful when you need a consistent return benchmark across several stocks or projects. If one model uses a different risk-free rate or market premium than another, the difference can look like an investment insight when it is really just an assumption mismatch.

If you need to estimate beta from matched stock and benchmark returns before using this model, start with the beta stock calculator.

The calculator follows the standard CAPM formula, then separates the market premium and beta-adjusted premium so the expected return is easier to audit.

• Risk-free rate: The base return assumption before adding compensation for market risk.
• Beta: The asset's sensitivity to broad market movement. A beta above 1 increases the market premium; a beta below 1 reduces it.
• Expected market return: The expected return on the market portfolio or benchmark used in the model.
• Forecast or required return: An optional comparison rate. The calculator subtracts CAPM expected return from this value to show alpha versus CAPM.

The market risk premium is the part of expected market return above the risk-free rate. Beta scales that premium. When beta is 1, the CAPM result equals the expected market return. When beta is 0, the CAPM result equals the risk-free rate.

The alpha output is a comparison, not a promise. It tells you whether your entered forecast or required return is higher or lower than the CAPM estimate using the same assumptions.

According to Association of Corporate Treasurers, CAPM can be expressed as Re = Rf + beta x (Rm - Rf), where Rf is the theoretical risk-free rate and Rm is the expected market return.

When the CAPM output becomes one input in a broader valuation rate, compare it with the assumptions in the discount rate calculator.

CAPM uses familiar finance terms, but each term needs a specific meaning before the result is worth using.

CAPM is not the same as a realized return measure. It gives an expected or required return from assumptions. A holding-period return, by contrast, measures what actually happened during a period, including the timing and income items you include.

The model also treats diversifiable company-specific risk differently from market risk. That is why beta is central: CAPM focuses on systematic risk rather than every possible risk attached to a company.

To compare this expected return with what an investment actually earned over time, use the holding period return calculator.

Use the CAPM calculator with one consistent set of assumptions for every asset you plan to compare. Mixing horizons or benchmarks weakens the result.

1. 1 Enter beta: Use the beta for the asset, company, portfolio, or project you are evaluating. Match the beta source to your benchmark where possible.
2. 2 Set the risk-free rate: Choose a rate assumption that fits the model horizon, then enter it as a percent.
3. 3 Enter expected market return: Use the expected return for the broad market benchmark behind your beta and investment case.
4. 4 Add a forecast return: Enter your expected, required, or analyst forecast return if you want the alpha comparison.
5. 5 Read the components: Check the market risk premium and beta-adjusted premium before relying on the final expected return.

For a valuation model, you might enter a 1.10 equity beta, a 4.25% risk-free rate, an 8.75% expected market return, and a 9.50% forecast return. The calculator shows whether that forecast clears the CAPM hurdle and where the hurdle came from.

A compact CAPM worksheet helps when you need the math visible, repeatable, and easy to challenge.

• • Clear return hurdle: The expected return output gives a specific hurdle for equity valuation, project screening, or investment review.
• • Assumption transparency: The separate market premium and beta-adjusted premium show whether the result is mainly driven by beta or by the market return assumption.
• • Comparable scenarios: Use the same risk-free rate and market return across several assets, then compare how beta changes the required return.
• • Forecast challenge: The alpha output makes it easier to ask whether a forecast return is enough for the market risk being assumed.
• • Model audit trail: Documenting each input helps reviewers understand why a valuation discount rate changed from one version to another.

The CAPM calculator is especially helpful before a more detailed valuation model. It gives you a cost-of-equity estimate to test, not a finished valuation conclusion. You can then decide whether the same discount rate belongs in a dividend, cash-flow, or scenario model.

For portfolio work, the output can support a quick discussion about whether a high expected return is compensation for high beta or a forecast that sits above the CAPM benchmark.

For dividend valuation work, the CAPM cost of equity can feed the required return used in the dividend discount model calculator.

Small input changes can move CAPM expected return materially. Treat each assumption as a documented modeling choice.

• • CAPM is a model, not a prediction engine. It does not include taxes, trading costs, liquidity limits, company-specific events, or whether beta will remain stable.
• • The calculator does not select the correct risk-free rate or expected market return for you. Those assumptions should come from your investment policy, valuation method, or research source.
• • A negative alpha result does not automatically mean an investment should be rejected; it means the entered forecast is below this CAPM hurdle.

Treasury yields are often used as risk-free-rate references, but the maturity should fit the use case. A long-term equity valuation normally needs a different horizon than a short-term trading note.

The SEC's investor education materials are a useful reminder that risk and return are linked, but not certain. CAPM gives a structured way to price one kind of risk; it does not remove investment uncertainty.

According to U.S. Department of the Treasury, Daily Treasury Par Yield Curve Rates are interpolated from the daily par yield curve at fixed maturities such as 1, 2, 3, 5, 7, 10, 20, and 30 years.

According to Investor.gov, all investments involve some degree of risk, and investors generally seek higher returns as investment risks rise.

If you want a simpler realized performance measure instead of a beta-based expected return, use the return on investment calculator.