How to Read the Option Chain: A Complete Guide

What Is an Option Chain and Why It Matters

The option chain is the most information rich screen in all of derivatives trading, and learning to read it well is one of the highest leverage skills a new options trader can build. In plain terms, an option chain is a live table published by the exchange that lists every option contract available for one underlying, such as the NIFTY 50 index or a stock like Reliance Industries, for a single expiry at a time. It shows you the price of each contract, how many are outstanding, how actively they are traded, and how the market is pricing the risk of future movement. Once you can read it, you stop guessing and start seeing what other participants are actually doing with their money.

On the National Stock Exchange (NSE), you can open the official option chain for free on the NSE website, and almost every broker terminal in India reproduces the same data inside its own trading screen. On a paper trading platform like First Plan India you can study the very same layout with zero money at risk, which is exactly how a beginner should start. Whatever the source, the structure is identical, so the habits you build here will transfer everywhere.

Why does this one screen matter so much? Because it answers four questions at once. What does each option cost right now? Where are large traders building or closing positions? How much movement is the market expecting? And which price levels are acting like a floor or a ceiling? A stock chart shows you the past. The option chain hints at what informed participants expect from the future, which is why professionals glance at it before almost every trade.

This guide builds from the ground up. We will start with the layout, then walk through each column one at a time: last traded price, open interest, change in open interest, volume, implied volatility, and the Greeks. After that we will define where a strike sits relative to the spot price, decode the bid and ask, and finally put everything together to read sentiment with full worked examples in NIFTY and BANKNIFTY. Treat this as study material and paper practice, not financial advice.

The Layout: Calls on the Left, Puts on the Right, Strikes in the Centre

Every option chain in India follows the same mirror layout, and memorising it once removes most of the early confusion. Down the exact middle of the table runs a single column of strike prices, listed from low at the top to high at the bottom. A strike price is simply the price at which the option holder has the right to buy or sell the underlying. For NIFTY you will see strikes spaced 50 points apart (for example 23900, 23950, 24000, 24050), while for BANKNIFTY they are usually 100 points apart.

Everything to the left of that central strike column belongs to the call options, often shortened to CE for Call European. Everything to the right belongs to the put options, shortened to PE for Put European. So a single horizontal row gives you the full picture for one strike: the call data on the left, the strike in the middle, and the put data on the right. Read across the row and you compare the call and the put at the same strike instantly.

Within the call side and the put side, the same columns repeat: open interest (OI), change in OI, volume, implied volatility (IV), last traded price (LTP), the net change in LTP, and the bid and ask quotes. The call columns are usually mirrored so that the values nearest the central strike sit closest to it, which is why the chain looks symmetrical. Do not let the symmetry fool you, the left and right sides tell very different stories.

One more rule that trips up beginners: an option chain shows one expiry at a time. At the top of the screen you select the expiry date, for example the nearest weekly expiry or the monthly expiry, and the entire table refreshes for that date. Among index options on the NSE, weekly expiries now exist only for the NIFTY 50, while BANKNIFTY and the other indices trade monthly contracts only. The same strike can carry completely different numbers across expiries, so always check which expiry you are viewing before you read anything else. NIFTY index options are cash settled, which means there is no delivery of shares, only a cash adjustment at expiry.

LTP: The Last Traded Price (Your Live Premium)

The last traded price, almost always labelled LTP, is the price at which the most recent trade in that option contract took place. For options, the LTP is the premium, the amount the buyer pays and the seller receives per unit of the underlying. It is the number most beginners look at first, and rightly so, because it is what you actually pay to enter a position.

Here is the key step many newcomers miss: the premium is quoted per unit, but you trade in lots. The NIFTY lot size used in this guide is 65 units (the exchange revises lot sizes periodically, so confirm the current size in the latest NSE circular before trading). So if the 24000 call (24000 CE) shows an LTP of ₹120, one lot will cost you 120 multiplied by 65, which is ₹7,800 in premium. If the 24000 put (24000 PE) shows an LTP of ₹110, one lot of that put costs 110 multiplied by 65, or ₹7,150. Always multiply the premium by the lot size to know your real outlay.

Next to the LTP sits a net change column, usually coloured green when the premium is higher than the previous close and red when it is lower. This tells you how the option has moved today. Be careful, a call premium and the underlying do not always move one to one, because time decay and volatility also push the premium around, a point we will return to when we discuss the Greeks.

The LTP is a record of the last trade, not a guarantee of your fill. In a fast market the next available price may differ, which is why the bid and ask, covered later, matter just as much. For a buyer, a quick mental check is the breakeven: a 24000 CE bought at ₹120 only profits at expiry above 24,120 (the strike plus the premium), while a 24000 PE bought at ₹110 profits below 23,890 (the strike minus the premium). The premium is never free, it is the hurdle your view must clear.

Open Interest (OI): How Many Contracts Are Live

Open interest, shown as OI, is the total number of option contracts at a given strike that are currently open, meaning they have been entered but not yet closed out, exercised, or expired. Every contract has a buyer and a seller, so OI counts the number of live agreements, not the number of trades. When a new buyer and a new seller create a fresh position, OI rises by one. When both sides close, OI falls by one.

Think of OI as the crowd size at a particular strike. A NIFTY 24000 CE showing 45 lakh OI means a very large number of open call positions sit at that level. High OI strikes are important for two practical reasons. First, they are usually the most liquid, so your orders fill easily with a tight spread. Second, the strikes where OI piles up tend to act as magnets and barriers for price, because so many participants have a stake there.

It helps to read OI in lots and in absolute terms. NSE typically reports OI in number of units, so if you see 45,50,000 for a strike with a 65 unit lot size, that works out to 70,000 lots outstanding. You do not need to do this maths every time, but understanding the scale stops you from misreading a thinly traded far strike as if it were a busy one.

A common beginner error is to treat high OI alone as bullish or bearish. By itself, OI is neutral. It only tells you that a lot of positions exist at that strike, not which direction the smart money expects. To extract a directional signal you must combine OI with price action and, even more importantly, with the change in OI, which is the subject of the next section.

Change in OI: Where Fresh Money Is Moving Today

If open interest is the crowd size, the change in OI is the crowd moving. This column shows how much OI rose or fell during the current session, and it is where the real story hides. A strike can carry huge standing OI from weeks ago, but the change in OI tells you where participants are committing or pulling money today, right now.

For directional instruments the classic framework pairs price with OI. Rising price with rising OI is a long buildup (fresh buyers, bullish). Falling price with rising OI is a short buildup (fresh sellers, bearish). Rising price with falling OI is short covering (sellers exiting, often a relief bounce). Falling price with falling OI is long unwinding (buyers exiting, a weakening trend). Keep these four pairings handy, they apply to futures and to reading the conviction behind a move.

On the option chain specifically, the most reliable reads come from combining the change in OI with the change in the premium at each strike. When call OI rises while the call premium falls, that points to call writing, sellers expecting price to stay below that strike, which marks it as resistance. When put OI rises while the put premium falls, that points to put writing, sellers expecting price to hold above that strike, which marks it as support. Writers are typically larger, better capitalised players, so where they plant their flags matters.

A worked read makes it concrete. Suppose with NIFTY near 24,000 the 24200 CE adds 9 lakh OI today while its premium slips, and the 23800 PE adds 7 lakh OI while its premium also slips. The message is that sellers are defending 24200 on the upside and 23800 on the downside, suggesting the market expects NIFTY to stay roughly inside that band into expiry. Always pair change in OI with the premium move, not the OI number alone.

Volume: Today's Activity at a Glance

Volume is the number of option contracts of a given strike that have been traded during the current session. Unlike open interest, which carries over from day to day, volume resets to zero at the start of every trading day. It is a measure of today's activity, how hot a particular strike is right now.

The cleanest way to keep the two straight: volume counts trades, OI counts open positions. A single contract can be bought and sold many times in a day, adding to volume each time, yet if it is opened and closed it leaves OI unchanged. High volume with rising OI means genuine new positioning. High volume with flat or falling OI often means intraday traders passing the same contracts back and forth.

Volume is your liquidity gauge for the session. Before you enter, glance at the volume on your chosen strike. A NIFTY at-the-money weekly option might show volume in the tens of lakhs, which means you can get in and out smoothly. A deep out-of-the-money strike three weeks from expiry might show almost nothing, which warns you that your order could move the price against you or simply sit unfilled.

Volume also flags fresh interest before OI fully reflects it. When a strike that was quiet suddenly lights up with heavy volume, something has caught the market's attention, perhaps a news event or a large player taking a view. Treat a sudden volume spike as a prompt to look closer, then confirm with the change in OI and the premium move before drawing a conclusion.

Implied Volatility (IV): How Expensive Options Are

Implied volatility, shown as IV in its own column, is the market's expectation of how much the underlying will move in the future, expressed as an annualised percentage. It is not measured directly. Instead it is backed out of the option premium using a pricing model, so IV is really the market collective opinion on future swings, baked into the price. A higher IV means traders expect bigger moves, a lower IV means they expect calm.

The practical takeaway is simple: high IV makes options expensive, and low IV makes them cheap. If the NIFTY 24000 CE carries an IV of 12 percent on a quiet day, the same option might jump to an IV of 20 percent the day before a major event, with its premium rising even if the index has not moved at all. That is the market charging more for uncertainty. IV says nothing about direction, only about the size of the expected move.

Indian traders should watch IV closely around scheduled events: company results, the Union Budget, RBI policy decisions, election outcomes, and global triggers. IV tends to climb into these events as demand for protection rises, then collapses sharply once the uncertainty resolves, a fall known as IV crush. Many beginners buy options just before results, get the direction right, and still lose money because the IV crush deflates their premium. Understanding this one effect saves a lot of pain.

Comparing IV across strikes reveals more. In Indian index options, out-of-the-money puts often carry a higher IV than equally distant calls, because traders pay up for downside protection. This pattern is called the volatility skew. You do not need to master skew on day one, but noticing that IV is not flat across the chain is the first step toward trading volatility rather than just direction. As a rule of thumb, option buyers prefer low IV (cheap entry) and option sellers prefer high IV (rich premium to collect).

The Greeks: Delta, Gamma, Theta, and Vega

The Greeks are a set of numbers that describe how an option premium will react to changes in the underlying, in time, and in volatility. Many option chains and broker terminals offer a Greeks view alongside the standard columns. You do not have to calculate them, but you must understand what they are telling you, because they explain why a premium moves the way it does.

Delta is the most used Greek. It measures how much the premium changes for a one point move in the underlying. Call deltas range from 0 to 1, put deltas from minus 1 to 0. An at-the-money option sits near 0.5, meaning a 10 point NIFTY move changes its premium by about 5 points. Delta doubles as a rough probability that the option finishes in the money, so a 0.30 delta call has roughly a 30 percent chance of expiring with value. Deep in-the-money options approach a delta of 1 and behave almost like the underlying itself.

Gamma measures how fast delta itself changes as the underlying moves. It is highest for at-the-money options and rises sharply as expiry approaches. High gamma is why weekly at-the-money options can swing violently in the final hours, a small index move flips them from nearly worthless to deeply in the money. Buyers love gamma for the explosive potential, sellers fear it for the same reason.

Theta is time decay, the amount of premium an option loses each day simply because expiry draws nearer, all else equal. Theta is negative for buyers (you lose) and positive for sellers (you gain). It accelerates as expiry nears and bites hardest on at-the-money options, which is precisely why selling weekly options to collect theta is popular, and also why it is risky when paired with high gamma. Vega, the fourth Greek, measures how much the premium changes for a one percentage point change in IV. When IV jumps before an event, high vega options gain even with no price move, and when IV crushes afterwards, they bleed. Read together, the Greeks turn the option chain from a static table into a living model of risk.

ITM, ATM, OTM: Where a Strike Sits Relative to Spot

Three labels you will hear constantly are in the money (ITM), at the money (ATM), and out of the money (OTM). They describe where a strike sits relative to the current spot price of the underlying, and they decide how much of an option premium is real value versus pure time value. Get these straight and most of the chain falls into place.

For a call option, a strike below the spot is in the money, a strike near the spot is at the money, and a strike above the spot is out of the money. For a put option it is the mirror image: a strike above the spot is in the money, a strike near the spot is at the money, and a strike below the spot is out of the money. With NIFTY at 24,000, the 23800 CE is ITM, the 24000 CE is ATM, and the 24200 CE is OTM, while the 24200 PE is ITM, the 24000 PE is ATM, and the 23800 PE is OTM.

Every premium splits into two parts: intrinsic value and time value. Intrinsic value is the amount by which an option is already in the money, and it can never be negative. With NIFTY at 24,000, a 23800 CE has 200 points of intrinsic value (24000 minus 23800). If that call trades at ₹260, then ₹200 is intrinsic and the remaining ₹60 is time value, the part that decays away by expiry. An ATM or OTM option has zero intrinsic value, so its entire premium is time value, which is why far OTM options can lose value fast.

Most option chains shade the in-the-money strikes with a light background, often a pale yellow, so you can spot them at a glance: ITM calls shade on the upper left, ITM puts shade on the lower right. Beginners tend to buy cheap deep OTM options because they cost little, not realising those are the strikes most likely to expire worthless. The trade off is real: ITM options cost more but move closely with the underlying, while OTM options are cheap but need a large, fast move just to break even.

Bid, Ask, and the Spread: The Real Cost of a Trade

The LTP tells you the last trade, but to actually deal you look at the bid and the ask. The bid is the highest price a buyer is currently willing to pay for the option, and the ask (sometimes called the offer) is the lowest price a seller is currently willing to accept. If you buy at market, you pay the ask. If you sell at market, you receive the bid. The LTP usually sits somewhere between the two.

The gap between the bid and the ask is the spread, and it is a hidden cost every trader pays. In a liquid at-the-money NIFTY weekly option, the spread might be just 5 to 25 paise wide, almost nothing. In an illiquid deep OTM strike far from expiry, the bid might be ₹2.00 and the ask ₹3.50, a spread so wide that you lose a chunk of your money the instant you enter and try to exit. A wide spread is the market telling you this contract is thinly traded, handle with care.

This is why order type matters. A market order fills immediately at the best available price, which is fine in liquid contracts but dangerous in wide spread ones, where you may pay far more than the LTP suggested. A limit order lets you name your price and wait, protecting you from slippage at the cost of possibly not filling. As a habit, prefer limit orders on anything but the most liquid strikes.

A quick example shows the bite. Say a strike shows a bid of ₹100 and an ask of ₹104. You buy one NIFTY lot at the ask, paying 104 multiplied by 65, which is ₹6,760. If you changed your mind a second later and sold at the bid of ₹100, you would receive 100 multiplied by 65, or ₹6,500. That ₹260 gap, before any brokerage or taxes, is the spread cost. Reading the bid and ask before you click is the difference between trading and donating.

Reading Sentiment: PCR, Support, Resistance, and Max Pain

Once the columns make sense, the option chain becomes a sentiment map. The single most useful read is the OI distribution. The strike with the highest call OI tends to act as resistance, because the call writers there are betting price stays below. The strike with the highest put OI tends to act as support, because the put writers are betting price stays above. Plot the heaviest call and put strikes and you have the market implied trading range for that expiry.

The Put Call Ratio, or PCR, condenses this into one number. It is the total put open interest divided by the total call open interest across the chain. A PCR above 1 means more puts are open than calls, often read as bullish (heavy put writing suggests sellers expect support to hold). A PCR below 1 means more calls are open, often read as bearish. The nuance is that PCR works best as a contrarian signal at extremes: a very high PCR can signal excessive optimism that precedes a fall, and a very low PCR can signal excessive fear that precedes a bounce.

Max pain is another concept drawn straight from OI. It is the strike price at which the total value of options expiring worthless is maximised, in other words the price at which option buyers as a group lose the most and writers lose the least. The theory, supported loosely by observation, is that price tends to gravitate toward the max pain strike as expiry approaches, because large writers have an incentive to defend it. Treat max pain as a soft magnet, not a precise prediction.

A word of caution keeps all of this honest. The option chain shows positioning, not certainty. OI can shift in minutes, writers can be wrong, and a strong news event will blow through any implied range. Use the chain to frame probabilities and to find levels, then confirm with price action and risk management. No single number on the chain is a buy or sell signal on its own, and none of this is a recommendation to trade.

Read the columns together and the wall of numbers becomes a clear conversation about price, positioning, and expectation.

Worked Example: Reading a NIFTY Option Chain Step by Step

Let us pull every column together with a realistic NIFTY snapshot. Assume the index spot is 24,000, it is a Monday with the NIFTY weekly expiry due the next day (Tuesday), and the chain shows the following around the money. The 23900 CE: LTP ₹165, OI 22 lakh, change in OI minus 3 lakh. The 24000 CE: LTP ₹95, OI 41 lakh, change in OI plus 9 lakh, IV 13 percent. The 24100 CE: LTP ₹48, OI 55 lakh, change in OI plus 14 lakh. On the put side, the 24000 PE: LTP ₹90, OI 38 lakh. The 23900 PE: LTP ₹52, OI 49 lakh, change in OI plus 12 lakh. The 23800 PE: LTP ₹28, OI 61 lakh, change in OI plus 16 lakh.

Start with structure. The spot is 24,000, so the 24000 strike is at the money, the 23900 CE is in the money, and the 24100 CE is out of the money. Now read the OI buildup. The heaviest, fastest growing call OI sits at 24100 (55 lakh, adding 14 lakh), and the heaviest, fastest growing put OI sits at 23800 (61 lakh, adding 16 lakh). That immediately frames an expected range of roughly 23800 to 24100 into tomorrow expiry, with resistance above and support below.

Next, weigh the premiums and costs. Buying one lot of the 24000 CE costs 95 multiplied by 65, which is ₹6,175, and its breakeven at expiry is 24,095. Buying one lot of the 23800 PE costs only 28 multiplied by 65, or ₹1,820, but it needs NIFTY to fall below 23,772 to profit, a move of more than 200 points in a single day. The cheap option is cheap for a reason: it is OTM with almost no intrinsic value and one day of life left, so theta will gut it fast unless the move comes quickly.

Finally, read the sentiment. Fresh OI is being added on both the 24100 calls and the 23800 puts, which means writers are selling both wings, expecting NIFTY to stay boxed in. With IV at a modest 13 percent, the market is not pricing a big surprise. A trader who understands the chain would conclude that buying far options for a breakout is fighting the writers and the clock, while the positioning favours range bound behaviour. Whether you act on that, and how you size and protect the trade, is where personal risk management and paper practice come in. This is study, not advice.

A BANKNIFTY Example and the Lot Size Difference

BANKNIFTY behaves like NIFTY more energetic cousin, and reading its chain reinforces the same skills with bigger numbers. The BANKNIFTY lot size used here is 30 units, and its strikes are typically spaced 100 points apart, reflecting its higher price and greater volatility. Because the index moves more, its option premiums are larger and its IV usually runs higher than NIFTY, so the rupee swings on a single lot are bigger.

Take a snapshot with BANKNIFTY at 52,000. Suppose the 52000 CE shows an LTP of ₹320 and the 52000 PE shows ₹300. One lot of the at-the-money call costs 320 multiplied by 30, which is ₹9,600, and one lot of the put costs 300 multiplied by 30, or ₹9,000. Compare that with the NIFTY at-the-money lot near ₹6,000 and you can feel why BANKNIFTY demands tighter risk control: the same percentage move translates into a larger rupee gain or loss per lot.

The reading process is identical. Find the spot, label the ITM, ATM, and OTM strikes, locate the heaviest call OI for resistance and the heaviest put OI for support, then check the change in OI to see where today money is flowing. If the 52500 CE is stacking call OI and the 51500 PE is stacking put OI, the writers are framing a 51500 to 52500 range. One important difference from NIFTY: BANKNIFTY no longer has weekly options, it trades only monthly contracts that expire on the last Tuesday of the month, so its chain reflects a longer time horizon than a NIFTY weekly.

One more practical note on settlement and instruments. NIFTY and BANKNIFTY options are index options and are cash settled, so you never take delivery, only a cash credit or debit at expiry. Single stock options, such as Reliance or HDFC Bank, are physically settled, meaning an in-the-money position carried to expiry can result in actual delivery of shares and a much larger margin requirement. Beginners should know this difference before holding any stock option into expiry.

Costs, Settlement, and India Specifics That Affect Your Read

Reading the chain correctly also means knowing what a trade really costs in India, because charges quietly change your breakeven. Securities Transaction Tax (STT) applies on the sell side of options and is charged on the premium, so it scales with how rich the option is. On top of that come brokerage (often a flat fee per executed order with discount brokers), exchange transaction charges, SEBI turnover fees, and state stamp duty on the buy side. Crucially, an 18 percent Goods and Services Tax (GST) is levied on the brokerage and transaction charges, not on your whole turnover, but it adds up over many trades.

These costs are small per trade yet decisive for high frequency intraday options trading, where a few rupees of edge can be swallowed entirely by charges. When you compute a breakeven from the chain, remember the textbook figure (strike plus premium for a call) is before costs, and your true breakeven is a touch further away. This is one more reason to favour liquid strikes with tight spreads, since the spread is often a larger cost than the brokerage itself.

On settlement, Indian cash equities settle on a T+1 basis, meaning shares and funds change hands one working day after the trade. Index options like NIFTY and BANKNIFTY are cash settled at expiry, with the difference between the strike and the settlement price credited or debited in cash, so there is no delivery to worry about. The settlement price for index options is based on an average of the underlying index over a defined window on expiry day, not a single tick, which protects against last second distortion.

Finally, keep the regulatory frame in mind. The exchanges (NSE and BSE) and the regulator (SEBI) periodically revise lot sizes, strike spacing, expiry schedules, and margin rules to keep the market orderly, especially for retail participants. As of this writing the NIFTY 50 lot is 65 units, BANKNIFTY is 30, and FINNIFTY is 60, with these monthly contract sizes revised down from earlier levels, so always verify the current contract specifications on the official NSE website before trading. On expiry timing, the NIFTY 50 carries both weekly and monthly contracts that expire on Tuesday (the weekly switched from Thursday to Tuesday on 1 September 2025), while BANKNIFTY and the other indices expire only on the last Tuesday of the month after their weekly contracts were discontinued. None of this is financial advice, it is the groundwork for informed, responsible learning.

Putting It All Together: A Repeatable Reading Routine

With every column now decoded, the goal is a routine you can run in under a minute whenever you open the option chain. Reading the chain is a skill, and like any skill it rewards a consistent checklist over scattered guessing. Here is a simple sequence that ties the whole guide together.

Notice how the columns reinforce one another. OI without change in OI is a snapshot without motion. IV without the Greeks tells you options are expensive but not how that will play out in your premium. Bid and ask without volume can lure you into an illiquid trap. The skill is not memorising any single number, it is reading them together until the chain tells you a coherent story about price, positioning, and expectation.

The fastest way to internalise all of this is to read a live option chain every day and place practice trades with no money at risk. On First Plan India you can study the real NSE layout, paper trade NIFTY and BANKNIFTY options, and watch how OI, IV, and the Greeks behave through an expiry without risking a rupee. Open the chain each morning, run the seven step routine below, and within a few weeks the wall of numbers becomes a clear conversation. Remember throughout that this guide is educational content to build your understanding, not financial advice or a recommendation to buy or sell any contract.

• Confirm the underlying and the exact expiry you are viewing, since the same strike differs across expiries.
• Note the spot price and label the ATM strike, then the nearby ITM and OTM strikes.
• Scan open interest to find the heaviest call strike (likely resistance) and the heaviest put strike (likely support).
• Read the change in OI together with the premium move to see where fresh writing or buying is happening today.
• Check IV to judge whether options are cheap or expensive, and whether a known event is near.
• Glance at volume, bid, and ask on your chosen strike to confirm it is liquid before you act.
• Translate the premium into rupees per lot and compute your real breakeven, including the spread.

Frequently asked questions

What is an option chain in simple words?

An option chain is a live table from the exchange that lists every call and put option for one underlying, such as NIFTY or a stock, at every strike price for a chosen expiry. Calls sit on the left, puts on the right, and strike prices run down the centre. For each option it shows the price (LTP), open interest, volume, implied volatility, and the bid and ask, so you can see what each contract costs and where traders are positioned.

What does OI mean in the option chain?

OI stands for open interest, the total number of option contracts at a strike that are currently open and not yet closed, exercised, or expired. It tells you how many live positions exist at that strike, which is a measure of crowd size and liquidity. High call OI often marks resistance and high put OI often marks support, but OI by itself is direction neutral until you read it with the change in OI.

What is the difference between OI and volume in options?

Volume counts how many contracts were traded during the current day and resets to zero each morning, while open interest counts how many positions are still open and carries over from day to day. A contract that is bought and then sold adds to volume but leaves OI unchanged. In short, volume measures today activity and OI measures standing commitment.

How do you read market sentiment from the option chain?

Look at where open interest is concentrated: the strike with the highest call OI tends to act as resistance and the highest put OI tends to act as support, which frames an expected range. Then read the change in OI with the premium move to see whether writers are selling calls (bearish) or puts (bullish) today. The Put Call Ratio adds a quick overall gauge, but treat extremes as contrarian and confirm with price action.

What does high IV mean in the option chain?

High implied volatility means the market expects large moves in the underlying, so option premiums are expensive on both the call and put side. IV usually rises before scheduled events like company results or RBI policy and then falls sharply afterwards, a drop called IV crush. High IV favours option sellers who collect rich premium, while option buyers prefer lower IV so their entry is cheaper.

What is the difference between ITM, ATM, and OTM options?

In the money (ITM) options already have intrinsic value: a call is ITM when the spot is above the strike and a put is ITM when the spot is below the strike. At the money (ATM) means the strike is near the current spot, and out of the money (OTM) means the option has no intrinsic value yet. ITM options cost more and track the underlying closely, while OTM options are cheap but need a fast, large move to become profitable.

Where can I see the NSE option chain for free?

The official NSE website publishes a free, live option chain for indices like NIFTY and BANKNIFTY and for individual stocks, and every broker terminal in India shows the same data. To practise reading it without risking money, you can use a paper trading platform such as First Plan India, which mirrors the real layout. Always check that you are viewing the correct underlying and expiry before drawing conclusions.

Why does a call option lose value even when the stock goes up?

A call premium is driven by more than just price. Time decay (theta) erodes value every day, and a fall in implied volatility (IV crush) can shrink the premium even on an up move, which is common right after results. If the rise is small and slow, theta and falling IV can outweigh the gain from delta. This is why buyers can be right on direction yet still lose, and why understanding the Greeks matters as much as the chart.