Understanding IV Rank and IV Percentile for Options Trading on Interactive Brokers

If you’re new to Interactive Brokers (IB) and options trading, you might have come across terms like IV Rank and IV Percentile on the platform and wondered what they mean. Don’t worry—this article is here to help! We’ll use a real example from National Grid PLC (NG), a stock on the London Stock Exchange, to explain these two numbers in a way that makes sense, even if you’ve never traded options before. By the end, you’ll understand what IV Rank and IV Percentile are telling you and how you can use them to decide whether to buy or sell an option on IB.

What Are Options, and Why Do These Numbers Matter?

First, a quick refresher: an option is like a ticket that lets you buy or sell a stock at a specific price by a certain date. For example, you might buy an option to buy National Grid stock at 1000 pence (GBp) by March 21, 2025. The price you pay for that option (called the premium) depends on how much the market thinks the stock price might move—something called implied volatility (IV). IV is a number that tells you how much the stock’s price is expected to wiggle up or down in the future. (If you want to learn more about IV, check out our other article on IV and HV!)

When you look at an options page on Interactive Brokers, like the one for National Grid, you’ll see two numbers called 52W IV Rank and 52W IV Percentile. These numbers help you understand if the options are cheap or expensive compared to the past year, which can help you decide if it’s a good time to buy or sell an option. Let’s break them down.

Step 1: What Is 52W IV Rank?

The 52W IV Rank tells you how big the current IV is compared to the highest and lowest IV over the past year (52 weeks). Think of it like a ruler: if the lowest IV in the past year is at 0 cm and the highest is at 100 cm, the IV Rank tells you where the current IV falls on that ruler, as a percentage.

• In our National Grid example, the current IV is 19.2%, the 52W IV Rank is 33, and the highest IV in the past year was 104.2%.
• This means the current IV (19.2%) is only 33% of the way between the lowest IV and the highest IV (104.2%) over the past year.
• In simple terms: the IV isn’t very high right now compared to the biggest it’s ever been. It’s closer to the low end of the ruler.

Step 2: What Is 52W IV Percentile?

The 52W IV Percentile tells you how often the IV was lower than it is now over the past year. Think of it like a calendar: imagine you have a calendar with 100 days, and you mark every day the IV was below the current IV. The percentile tells you what percentage of those days had a lower IV.

• For National Grid, the current IV is 19.2%, and the 52W IV Percentile is 62%.
• This means that on 62% of the days in the past year, the IV was lower than 19.2%.
• In simple terms: the IV is higher now than it was on most days last year. On our calendar, if we had 100 days, 62 of them would have an IV below 19.2%.

Step 3: Why Do These Numbers Look Different?

You might be wondering: “Wait, the IV Rank (33) says options are cheap, but the IV Percentile (62%) says they’re a bit expensive. Which is it?” Don’t worry—they’re not arguing with each other! They’re just looking at the same thing (IV) in two different ways:

• IV Rank is like a ruler: it compares the current IV to the biggest and smallest IV over the past year. National Grid’s IV got as high as 104.2% last year, so 19.2% looks low on that ruler (33%).
• IV Percentile is like a calendar: it checks how many days the IV was lower than 19.2%. Since it was lower on 62% of days, 19.2% looks a bit high compared to a typical day.

Here’s why this happens: National Grid’s IV was probably very low (like 10%-15%) on most days last year, but there were a few days when it shot up to 104.2% (maybe during a big news event). So, the current IV (19.2%) is low compared to that huge spike (low IV Rank), but higher than the usual calm days (higher IV Percentile).

Step 4: How to Use IV Rank and IV Percentile on Interactive Brokers

Now that you know what these numbers mean, let’s see how you can use them on IB to make a simple decision. Let’s look at National Grid’s options page on IB (see the screenshot):

• Stock Price: National Grid is at 971.20 pence (GBp).
• Options Chain: This shows different prices (called “strikes”) where you can buy or sell options. For example, you can buy a “call” option to buy the stock at 1000 pence by March 21, 2025.
• IV Rank: 33 (low, so options are cheaper compared to the highest IV last year).
• IV Percentile: 62% (higher, so options are a bit more expensive than most days last year).

Scenario 1: Buying an Option (You Think the Stock Will Go Up)

• Let’s say you think National Grid’s price will jump to 1050 pence by March because of some good news.
• You look at the options chain and see a “call” option at the 1000 strike for March 21, 2025. The price to buy it (the “ask”) is 35.50 pence per share (since options are usually for 100 shares, that’s 35.50 x 100 = £35.50 total).
• The low IV Rank (33) tells you this option is cheaper than it would be if IV were super high (like 104.2%). This is a good deal if you think the stock will move a lot—your ticket is affordable!
• What to do on IB: Click on the “35.50” under the “Ask” column for the 1000 strike call, then click the “Trade” button at the bottom of the screen. This lets you buy the option.

Scenario 2: Selling an Option (You Think the Stock Won’t Move Much)

• Let’s say you think National Grid’s price will stay around 971 pence and won’t move much by March.
• You see the same 1000 strike call option, but now you want to sell it. The price you’ll get (the “bid”) is 33.50 pence per share (£33.50 for 100 shares).
• The higher IV Percentile (62%) tells you the option’s price is a bit more expensive than most days last year, so you’ll get more money for selling it now.
• What to do on IB: Click on the “33.50” under the “Bid” column for the 1000 strike call, then click the “Trade” button. Choose “Sell” to collect the £33.50.

Step 5: Putting It All Together

Here’s the big picture:

• IV Rank (33): If it’s low, like here, options are cheaper compared to the biggest IV last year. This is good for buying options if you think the stock will move a lot.
• IV Percentile (62%): If it’s higher, like here, options are a bit more expensive than most days last year. This is good for selling options because you get more money.
• How to decide: Look at both numbers and think about what you expect the stock to do. If you think National Grid will jump up or down a lot, the low IV Rank means it’s a good time to buy. If you think it’ll stay steady, the higher IV Percentile means it’s a good time to sell.

Final Tip for Beginners

When you’re starting out on Interactive Brokers, don’t stress about getting everything perfect. IV Rank and IV Percentile are just tools to help you see if options are cheap or expensive compared to the past. Start with small trades to practice—like buying or selling one option contract (100 shares)—and watch how the stock moves. Over time, you’ll get more comfortable using these numbers to make decisions!