How much a stock price moves can help investors analyze its historical risk and price behavior. The Stock Volatility Calculator is a simple online tool that calculates volatility from historical stock price data. It calculates daily volatility using price-to-price returns and converts it into annualized volatility using 252 trading days. Interactive charts make it easier to study price movements.
Stock Volatility Calculator
Calculate daily, annualized and rolling volatility from historical stock prices or OHLC data.
Historical Price Data
You can paste one closing price per line, NSE data, or a CSV containing Date, Close, Open, High and Low columns.
Daily Volatility
—
Standard deviation of daily returns
Annualized Volatility
—
Daily volatility × √252
Latest Price
—
Latest chronological close
Price Change
—
From first to latest price
Calculation Period
—
Price Chart
Daily Returns
Rolling Volatility
Return Distribution
Information → How volatility is calculated
Daily Return
(Today's Close − Previous Close) ÷ Previous Close
Daily Volatility
Daily volatility is the standard deviation of the daily price-to-price returns.
Annualized Volatility
Annualized volatility estimates yearly volatility by multiplying daily volatility by √252, using 252 as the approximate number of trading sessions in a year.
Rolling Volatility
Rolling volatility measures the standard deviation of returns over a selected moving window, such as 5, 10, 20, or 30 trading days.
Return Distribution
Return distribution shows how the daily price-to-price returns are distributed across different percentage ranges.
Calculation notes
- At least 3 valid closing prices are required.
- Prices must be positive numbers.
- When dates are available, the data is automatically sorted chronologically.
- When OHLC data is available with valid dates, a candlestick chart is shown.
- If only closing prices are available, the tool automatically uses a close-price line chart.
How to Calculate Stock Volatility?
Enter Data
Paste historical stock prices or upload compatible CSV/TXT data into the calculator.
Check Data
The tool detects price columns and organizes dated data in the correct chronological order.
Calculate
Click Calculate Volatility to calculate daily and annualized stock price volatility.
Analyze Results
Review the dashboard, calculation period, trading days, returns, and volatility charts.
Features
Daily Volatility
Measure the standard deviation of daily price-to-price returns.
Annualized Volatility
Convert daily volatility into annualized volatility using 252 trading days.
Calculation Period
See the exact start and end dates used for the volatility calculation.
Trading Days
View the number of trading-price observations included in the calculation.
Returns & Charts
Analyze daily returns, price movement, rolling volatility, and return distribution visually.
Smart Data Detection
Automatically detect common Date, Open, High, Low, and Close columns from your data.
Frequently Asked Questions
What is a stock volatility calculator?
A stock volatility calculator is an online tool that measures the historical stock's price using past price data. It helps you understand how much the stock price has fluctuated during a selected period.
How do I calculate daily volatility?
Daily volatility can be calculated by price-to-price returns between consecutive trading days and then calculating the standard deviation of those returns. The calculator performs these calculations automatically.
How do I calculate annualized volatility?
Annualized volatility can be estimated by multiplying daily volatility by the square root of the number of trading days in a year. Using the common 252-trading-day.
What data can I use with this calculator?
You can paste historical stock price data manually or use CSV or TXT data. The calculator can detect common Date, Open, High, Low, and Close columns and use the appropriate price information.
What is rolling volatility?
Rolling volatility measures volatility over a moving window of recent observations. The calculator provides selectable rolling periods such as 5, 10, 20, and 30 days.
What charts are available in the calculator?
The calculator provides charts for price movement, daily returns, rolling volatility, and return distribution. Depending on the available data.
Does the calculator use price-to-price returns?
Yes. The volatility calculation is based on price-to-price returns between consecutive observations. This allows the calculator to measure how much returns have historically varied during the selected period.
