--- title: "Realized Variance: Formula, Meaning" description: "Realized variance is the sum of squared returns over a period, typically built from intraday or daily returns. It is the basic building block of realized..." canonical: https://www.getswoopr.com/indicators/volatility/realized-variance/ source: "Swoopr Investment: https://www.getswoopr.com" --- ## Direct Answer > Realized variance is the sum of squared returns over a period, typically built from intraday or daily returns. It is the basic building block of realized volatility and is the quantity variance swaps settle on. It is in squared-return units and adds up over time, so a longer window gives a larger number. # Realized Variance: Formula, Meaning, Signals, Examples and How to Use It ## How Is Realized Variance Calculated? Realized variance is the sum of squared returns over a period, typically built from intraday or daily returns. It is the basic building block of realized volatility and is the quantity variance swaps settle on. **Formula:** `RV = sum of r_i^2 over the period` **Inputs:** - A series of log returns r_i - The period being measured **Worked example.** Returns of 1.0%, -2.0% and 1.5% give a realized variance of 0.000725. The inputs are illustrative numbers, not market data. **Reading it.** It is in squared-return units and adds up over time, so a longer window gives a larger number. To compare with implied volatility, scale it to an annual rate and take the square root. **Limits.** It includes jumps and, at very high sampling frequencies, microstructure noise, so the sampling interval matters. Squaring emphasizes large moves, so one big day can dominate. ## What is Realized Variance? Realized variance is the sum of squared returns over a period, typically built from intraday or daily returns. It is the basic building block of realized volatility and is the quantity variance swaps settle on. ## How to use Realized Variance It is in squared-return units and adds up over time, so a longer window gives a larger number. To compare with implied volatility, scale it to an annual rate and take the square root. A reading alone is never a buy or sell signal; it needs context from price structure, volume, volatility and the broader market regime. ## Strengths - Summing squared returns needs no model and no mean adjustment, so it is a direct tally of how much price moved. - Sums of squared returns are additive over time, so daily values can be accumulated into weekly or monthly variance. - Reproducible when the formula and data convention are fixed. ## Weaknesses and limitations - It carries squared units and grows with the number of observations in the period, so periods of different lengths cannot be compared directly. - It mixes continuous movement and jumps into one total, so it cannot show which part came from sudden moves. - Correlated indicators can create false confidence by repeating the same underlying information. ## Editorial and risk note This page is educational content, not individualized investment advice. It should not imply guaranteed prediction, accuracy or outperformance. ## Frequently Asked Questions Is Realized Variance a buy or sell signal? No. It is in squared-return units and adds up over time, so a longer window gives a larger number. It includes jumps and, at very high sampling frequencies, microstructure noise, so the sampling interval matters. A trade built on it still needs a trigger, an invalidation rule, a position size and realistic execution assumptions. What is the best setting for Realized Variance? Realized Variance takes these inputs: a series of log returns r_i; the period being measured. There is no universal best setting for the tunable ones, so test them across instruments, regimes and out-of-sample periods and favor stable parameter regions over one historical winner. Can Realized Variance be used by itself? It includes jumps and, at very high sampling frequencies, microstructure noise, so the sampling interval matters. Squaring emphasizes large moves, so one big day can dominate. For that reason it is read next to measures of direction, participation, valuation, liquidity and risk, not alone. Does Realized Variance work on every timeframe? The calculation (RV = sum of r_i^2 over the period) can be run on any bar size, but behavior is not portable: a reading on a five-minute chart describes a very different market window from the same reading on a daily chart. Validate the exact timeframe before relying on it. Why does Realized Variance give false signals? It carries squared units and grows with the number of observations in the period, so periods of different lengths cannot be compared directly. It mixes continuous movement and jumps into one total, so it cannot show which part came from sudden moves. Lag, noise and regime changes add to this, because market participants react to new information after the reading is calculated. How should Realized Variance be backtested? Rebuild Realized Variance from a series of log returns r_i using point-in-time data, write the rules before testing, include delisted securities where relevant, model realistic fills and costs, reserve a validation sample and compare with a simpler baseline. ## References - [Econometrica: Modeling and Forecasting Realized Volatility (Andersen, Bollerslev, Diebold and Labys, 2003)](https://doi.org/10.1111/1468-0262.00418) S Swoopr Editorial Team The Swoopr Editorial Team produces independent investment education, research, and tools for understanding markets, evaluating opportunities, and managing risk. All content is educational only and does not constitute personalized investment advice. See our [editorial policy](https://www.getswoopr.com/legal/editorial-policy/) and [corrections policy](https://www.getswoopr.com/legal/corrections-policy/).