Understanding Implied Volatility

What is Implied Volatility?

We have already seen that option premiums are affected by several factors, including:

• Underlying price
• Strike Price
• Time to expiry
• Volatility

But there is a practical challenge.

We know the option's market price, but we do not directly know the volatility that the market is using to value that option.

This is where Implied Volatility (IV) comes in.

Implied Volatility is the volatility value that, when used in an option pricing model along with the other known inputs, produces the option's current market price.

In simple words:

Option Price → Pricing Model → Implied Volatility

IV Is Forward-Looking

Historical Volatility tells us how much the underlying has moved in the past.

Implied Volatility is different.

It reflects the volatility that is implied by current option prices and therefore provides an indication of the market's expectations about future movement.

For example, if traders expect a major event to cause large price swings, option premiums may rise.

This can result in higher Implied Volatility.

A Simple Example

Suppose an option has:

• Current market price: ₹100
• Underlying price: ₹1,000
• Strike Price: ₹1,050
• Time to expiry: 30 days

The other inputs are known.

The only unknown input is volatility.

If a pricing model shows that a volatility of 25% produces an option value of ₹100, then:

Implied Volatility = 25%

This does not mean the underlying will definitely move by 25%.

It simply means that 25% volatility is implied by the current option price under the model's assumptions.

Why Does IV Change?

Implied Volatility changes because option prices change.

Option prices can rise or fall because market participants change their expectations about future price movement.

IV may increase when:

• Uncertainty increases
• A major event is approaching
• Traders expect larger price movements
• Demand for options increases

IV may decrease when:

• Uncertainty reduces
• The event passes
• Expected price movement decreases
• Demand for options falls

Therefore, IV is not a fixed number.

It changes continuously with market conditions.

IV and Option Premium

There is generally a positive relationship between IV and option premium.

When IV rises

Option Premium generally rises

When IV falls

Option Premium generally falls

This applies to both Call and Put Options.

Therefore, a trader buying an option is generally helped by an increase in IV, while an option seller generally benefits when IV decreases.

IV Is Not a Direction Indicator

One important point is that Implied Volatility does not tell you whether the underlying will rise or fall.

High IV means the market is pricing in greater expected movement.

It does not tell us whether that movement will be:

• Upward
• Downward
• Or highly volatile in both directions

For example:

High IV = Greater Expected Movement

It does not mean:

High IV = Bullish Market

Similarly:

Low IV = Lower Expected Movement

It does not mean:

Low IV = Bearish Market

IV and Market Events

Implied Volatility often becomes important around major market events.

Examples include:

• Company results
• Important economic announcements
• Major policy decisions
• Elections
• Significant corporate developments

Before such events, traders may expect larger-than-normal price movements.

This can push IV higher.

After the event passes and uncertainty reduces, IV can fall sharply.

This sudden decline in volatility is often called a volatility crush.

Understanding Volatility Crush

Suppose an option is trading at a high premium before an important event.

The premium may contain significant volatility value because traders expect a large move.

The event occurs.

But the actual price movement turns out to be smaller than expected.

Once the uncertainty disappears, IV can decline sharply.

As IV falls, the option premium can also fall.

This can happen even when the underlying moves in the direction the trader expected.

Practical Example

Suppose you buy a Call before an important event.

You expect the stock to rise.

The stock does rise after the event.

However:

• The event has already passed.
• Uncertainty has reduced.
• IV falls significantly.

The rise in the underlying may increase the Call's value, but the fall in IV may reduce it.

The final result depends on the combined impact of all option pricing factors.

This is why traders should not evaluate an option only by looking at the direction of the underlying.

IV Rank and IV Percentile

Traders sometimes compare the current IV with its historical levels.

Two commonly used approaches are:

IV Rank

It compares the current IV with the highest and lowest IV observed over a particular historical period.

IV Percentile

It measures how often the historical IV was below the current IV during a particular period.

These measures help traders understand whether current volatility is relatively high or low compared with its past levels.

However, they should be used as context, not as standalone buy or sell signals.

Practical Insight

When evaluating an option, ask:

Is the current IV high or low compared with its historical levels?

Then ask:

What could cause IV to rise or fall from here?

This can help traders understand whether the option premium may be expensive or relatively inexpensive from a volatility perspective.

Common Beginner Mistake

A common mistake is assuming that a high IV automatically means an option is a good opportunity to sell.

High IV can mean higher premiums, but it also indicates that the market expects greater uncertainty and potentially larger price movements.

Higher premium comes with higher potential risk.

Therefore:

High IV ≠ Guaranteed Profit

Key Insight

Implied Volatility represents the volatility embedded in the current option price.

It reflects market expectations about future movement, but it does not predict the direction of that movement.

Key Takeaways

• Implied Volatility (IV) is derived from the current option price.
• It reflects the volatility level implied by the market.
• IV is generally forward-looking, unlike Historical Volatility.
• Higher IV generally increases Call and Put premiums.
• Lower IV generally reduces option premiums.
• IV does not indicate whether the underlying will rise or fall.
• Major events can cause IV to rise because uncertainty increases.
• IV can fall sharply after an event when uncertainty disappears.
• A sharp fall in IV is commonly called a volatility crush.
• IV Rank and IV Percentile help compare current IV with historical levels.
• High IV can mean higher premiums, but it also comes with higher uncertainty and risk.