Historical Volatility Calculator

This tool helps traders and options strategists calculate the historical volatility of a security based on past price data. It is designed to provide insights into market trends and potential price movements.

Calculator

Results

Historical Volatility -

Data Source and Methodology

Data for calculations are derived from historical market prices. All calculations are based on industry-standard methodologies and formulas.

All calculations strictly adhere to the methodologies and data provided by these sources.

The Formula Explained

Historical Volatility Formula:

\[\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}\]

Where \(\sigma\) is the standard deviation of returns, \(R_i\) is the log return of day \(i\), and \(\bar{R}\) is the average return.

Glossary of Variables

  • Price Data: Historical prices of the security.
  • Volatility: A measure of price fluctuations over time.

How It Works: A Step-by-Step Example

Suppose you have price data for a stock over the last five days: 100, 105, 102, 108, and 107. You can enter these values into the calculator to determine the historical volatility, which indicates the stock's past price fluctuations.

Frequently Asked Questions (FAQ)

What is historical volatility?

Historical volatility measures the past price fluctuations of a security within a specific time period.

How is historical volatility used in trading?

Traders use historical volatility to evaluate risk and to set options pricing, among other strategies.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
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Formula (extracted LaTeX)
\[\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}\]
\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}
Formula (extracted text)
Historical Volatility Formula: \[\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}\] Where \(\sigma\) is the standard deviation of returns, \(R_i\) is the log return of day \(i\), and \(\bar{R}\) is the average return.
Variables and units
  • T = property tax (annual or monthly depending on input) (currency)
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn
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Historical Volatility Calculator

This tool helps traders and options strategists calculate the historical volatility of a security based on past price data. It is designed to provide insights into market trends and potential price movements.

Calculator

Results

Historical Volatility -

Data Source and Methodology

Data for calculations are derived from historical market prices. All calculations are based on industry-standard methodologies and formulas.

All calculations strictly adhere to the methodologies and data provided by these sources.

The Formula Explained

Historical Volatility Formula:

\[\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}\]

Where \(\sigma\) is the standard deviation of returns, \(R_i\) is the log return of day \(i\), and \(\bar{R}\) is the average return.

Glossary of Variables

  • Price Data: Historical prices of the security.
  • Volatility: A measure of price fluctuations over time.

How It Works: A Step-by-Step Example

Suppose you have price data for a stock over the last five days: 100, 105, 102, 108, and 107. You can enter these values into the calculator to determine the historical volatility, which indicates the stock's past price fluctuations.

Frequently Asked Questions (FAQ)

What is historical volatility?

Historical volatility measures the past price fluctuations of a security within a specific time period.

How is historical volatility used in trading?

Traders use historical volatility to evaluate risk and to set options pricing, among other strategies.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
\[','\]
','
Formula (extracted LaTeX)
\[\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}\]
\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}
Formula (extracted text)
Historical Volatility Formula: \[\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}\] Where \(\sigma\) is the standard deviation of returns, \(R_i\) is the log return of day \(i\), and \(\bar{R}\) is the average return.
Variables and units
  • T = property tax (annual or monthly depending on input) (currency)
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn
``` ]], displayMath: [['\\[','\\]']] }, svg: { fontCache: 'global' } };, svg: { fontCache: 'global' } };

Historical Volatility Calculator

This tool helps traders and options strategists calculate the historical volatility of a security based on past price data. It is designed to provide insights into market trends and potential price movements.

Calculator

Results

Historical Volatility -

Data Source and Methodology

Data for calculations are derived from historical market prices. All calculations are based on industry-standard methodologies and formulas.

All calculations strictly adhere to the methodologies and data provided by these sources.

The Formula Explained

Historical Volatility Formula:

\[\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}\]

Where \(\sigma\) is the standard deviation of returns, \(R_i\) is the log return of day \(i\), and \(\bar{R}\) is the average return.

Glossary of Variables

  • Price Data: Historical prices of the security.
  • Volatility: A measure of price fluctuations over time.

How It Works: A Step-by-Step Example

Suppose you have price data for a stock over the last five days: 100, 105, 102, 108, and 107. You can enter these values into the calculator to determine the historical volatility, which indicates the stock's past price fluctuations.

Frequently Asked Questions (FAQ)

What is historical volatility?

Historical volatility measures the past price fluctuations of a security within a specific time period.

How is historical volatility used in trading?

Traders use historical volatility to evaluate risk and to set options pricing, among other strategies.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
\[','\]
','
Formula (extracted LaTeX)
\[\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}\]
\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}
Formula (extracted text)
Historical Volatility Formula: \[\sigma = \sqrt{\frac{\sum_{i=1}^{n} (R_i - \bar{R})^2}{n - 1}}\] Where \(\sigma\) is the standard deviation of returns, \(R_i\) is the log return of day \(i\), and \(\bar{R}\) is the average return.
Variables and units
  • T = property tax (annual or monthly depending on input) (currency)
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn
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