Beta Calculator Guide
Use this beta calculator to estimate an assets market sensitivity from asset returns and benchmark market returns, including beta, alpha, correlation, R-squared, and systematic risk.
How to use the beta calculator
Enter matching asset return and market return data for the same periods. The calculator estimates beta from covariance and market variance, then shows regression, rolling beta, up-market beta, down-market beta, and risk decomposition.
Use monthly or periodic returns from the same time frame for both the asset and benchmark. More observations usually produce a more reliable beta estimate.
Beta formula
The beta formula is: Beta = Covariance of Asset and Market Returns / Variance of Market Returns. Beta is the slope of the regression line between asset returns and market returns.
A beta of 1.0 means the asset has moved roughly with the market. A beta above 1.0 suggests higher market sensitivity, while a beta below 1.0 suggests lower market sensitivity.
How to interpret beta
A defensive asset may have a beta below 1.0, meaning it historically moved less than the market. A growth or cyclical asset may have a beta above 1.0, meaning it historically amplified market movements.
Negative beta is uncommon and means the asset has tended to move opposite the market during the measured period.
Beta, alpha, and R-squared
Alpha measures the average return not explained by market movement in the regression. R-squared shows how much of the assets return variation is explained by the market benchmark.
A beta estimate with low R-squared may be less useful because the benchmark explains only a small share of the assets movement.
Common beta analysis mistakes
The most common mistake is using mismatched return periods or an irrelevant benchmark. Asset returns and market returns must cover the same dates and frequency.
Another mistake is treating historical beta as permanent. Beta can change when leverage, business mix, interest rates, or market conditions change.
- Use the same return frequency for asset and benchmark.
- Choose a benchmark that fits the asset.
- Use enough observations for a meaningful regression.
- Review rolling beta when risk may be changing over time.