Basics

Beta

By Ryan Silk & Lawrence Polatchek · Reviewed April 2026 · Options Trading Glossary

Stock volatility relative to the market

What is Beta?

Beta A measure of a stock's volatility relative to the overall market (typically the S&P 500). A beta of 1.0 means the stock moves with the market. Beta above 1.0 indicates higher volatility; below 1.0 indicates lower volatility. High-beta stocks typically have higher implied volatility and more expensive options.

Complete Definition

A measure of a stock's volatility relative to the overall market (typically the S&P 500). A beta of 1.0 means the stock moves with the market. Beta above 1.0 indicates higher volatility; below 1.0 indicates lower volatility. High-beta stocks typically have higher implied volatility and more expensive options.

Example

A stock with beta 1.5 tends to move 1.5% for every 1% market move, resulting in more expensive options premiums.

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Written by
ApexVol Research Team
Quantitative options research
All calculations use live ORATS institutional data — the same source used by professional volatility desks.
RS
Technical reviewer
Ryan Silk, ApexVol Founder
Reviewed for technical accuracy
10+ years trading options. Built ApexVol's pricing engine, Greeks model, and IV-rank methodology.
This guide is updated as market conditions and ORATS data change. Last revised 2026-05-12. How we research →

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