Options questions, answered

Open interest is the total number of option contracts in a strike that are still open and not yet squared off or settled. It counts positions, not trades. Rising open interest means fresh contracts are being created and new money is entering that strike; falling open interest means existing positions are being closed out.

Look for the strikes carrying the largest put and call open interest around the current spot. The heaviest put strike below spot is commonly treated as a support reference and the heaviest call strike above spot as resistance. Then watch change in open interest through the session — a level being defended will keep adding open interest, while a level about to break usually sheds it.

Change in open interest shows what is happening today, while standing open interest shows what was already there. A strike can hold a very large position built up over weeks yet see no fresh activity, and another can be quiet in absolute terms but adding aggressively right now. Reading both together separates old positioning from live intent.

Volume counts every contract traded during the session and resets to zero the next day, while open interest counts contracts still outstanding and carries forward until they are closed or expire. High volume with rising open interest points to fresh positioning; high volume with falling open interest points to existing positions being unwound.

Implied volatility is set by supply and demand for each contract separately, so the same strike can price its call and its put differently. Persistent gaps usually reflect directional demand — heavier put buying lifts put implied volatility, producing the downside skew commonly seen in index options. Watching the gap widen or narrow is itself a read on positioning.

Open interest is the total number of option contracts in a strike that are still open and not yet squared off or settled. It counts positions, not trades. Rising open interest means fresh contracts are being created and new money is entering that strike; falling open interest means existing positions are being closed out.

Look for the strikes carrying the largest put and call open interest around the current spot. The heaviest put strike below spot is commonly treated as a support reference and the heaviest call strike above spot as resistance. Then watch change in open interest through the session — a level being defended will keep adding open interest, while a level about to break usually sheds it.

Change in open interest shows what is happening today, while standing open interest shows what was already there. A strike can hold a very large position built up over weeks yet see no fresh activity, and another can be quiet in absolute terms but adding aggressively right now. Reading both together separates old positioning from live intent.

Volume counts every contract traded during the session and resets to zero the next day, while open interest counts contracts still outstanding and carries forward until they are closed or expire. High volume with rising open interest points to fresh positioning; high volume with falling open interest points to existing positions being unwound.

Implied volatility is set by supply and demand for each contract separately, so the same strike can price its call and its put differently. Persistent gaps usually reflect directional demand — heavier put buying lifts put implied volatility, producing the downside skew commonly seen in index options. Watching the gap widen or narrow is itself a read on positioning.

Open interest is the total number of option contracts in a strike that are still open and not yet squared off or settled. It counts positions, not trades. Rising open interest means fresh contracts are being created and new money is entering that strike; falling open interest means existing positions are being closed out.

Look for the strikes carrying the largest put and call open interest around the current spot. The heaviest put strike below spot is commonly treated as a support reference and the heaviest call strike above spot as resistance. Then watch change in open interest through the session — a level being defended will keep adding open interest, while a level about to break usually sheds it.

Change in open interest shows what is happening today, while standing open interest shows what was already there. A strike can hold a very large position built up over weeks yet see no fresh activity, and another can be quiet in absolute terms but adding aggressively right now. Reading both together separates old positioning from live intent.

Volume counts every contract traded during the session and resets to zero the next day, while open interest counts contracts still outstanding and carries forward until they are closed or expire. High volume with rising open interest points to fresh positioning; high volume with falling open interest points to existing positions being unwound.

Implied volatility is set by supply and demand for each contract separately, so the same strike can price its call and its put differently. Persistent gaps usually reflect directional demand — heavier put buying lifts put implied volatility, producing the downside skew commonly seen in index options. Watching the gap widen or narrow is itself a read on positioning.

Read it in two directions. Scanning down a single time column shows how open interest is distributed across strikes at that moment. Scanning across a single strike row shows whether that strike is filling up or emptying out over time. The strongest reads come from rows that darken steadily while spot approaches them.

High open interest marks where positioning is concentrated, and those strikes often behave as reference levels — heavy call open interest above spot is commonly read as resistance and heavy put open interest below spot as support. This is a crowding observation, not a rule. Levels can and do break, usually when that open interest unwinds quickly.

Migration means the crowd is repositioning rather than defending. When the heavy call band shifts to higher strikes through the session, positions at the old level are being closed and rebuilt further away, which usually follows a move that broke through it. The direction of migration frequently confirms a trend that price alone shows ambiguously.

Open interest is the total number of option contracts in a strike that are still open and not yet squared off or settled. It counts positions, not trades. Rising open interest means fresh contracts are being created and new money is entering that strike; falling open interest means existing positions are being closed out.

Both views are available, and they answer different questions. Total open interest shows the standing book and highlights durable levels built over days. Change in open interest highlights only fresh activity and reacts much faster, which makes it the better view for reading what is being added or abandoned right now.

There is no single good value — put-call ratio is read relative to its own recent range, not against a fixed number. A PCR near 1 suggests balanced call and put open interest. Readings well above the recent range are usually treated as put-heavy positioning, and readings well below as call-heavy. Direction of change matters more than the level.

An OI crossover is the point where total put open interest moves above total call open interest, or falls back below it, flipping which side of the book is heavier. It is the same event as the ratio passing 1.00, which is why it is marked on the PCR line itself. It matters because it marks a change in where the crowd is positioned rather than a change in price. Crossovers around key levels often coincide with a shift in intraday character.

On its own it is context, not a signal. Crossovers are most informative when they line up with something else — price reclaiming a level, a build at a nearby strike, or a shift in max pain. A crossover that happens on thin open interest, or one that reverses within minutes, usually reflects noise in the totals rather than a genuine change in positioning.

Both, and they answer different questions. PCR on total open interest describes the standing book, which moves slowly and reflects accumulated positioning. PCR on change in open interest describes what is being added today and reacts far faster. Intraday reads lean on the change-based ratio; positional reads lean on the total.

Volume counts every contract traded during the session and resets to zero the next day, while open interest counts contracts still outstanding and carries forward until they are closed or expire. High volume with rising open interest points to fresh positioning; high volume with falling open interest points to existing positions being unwound.

No. PCR is a positioning statistic, not a signal — it describes how the option book is arranged, not where price is going. It is most useful as context alongside price structure and the open-interest distribution across strikes. Extreme readings tend to mark crowded positioning, and crowded positioning can persist far longer than expected.

Open interest is the total number of option contracts in a strike that are still open and not yet squared off or settled. It counts positions, not trades. Rising open interest means fresh contracts are being created and new money is entering that strike; falling open interest means existing positions are being closed out.

Look for the strikes carrying the largest put and call open interest around the current spot. The heaviest put strike below spot is commonly treated as a support reference and the heaviest call strike above spot as resistance. Then watch change in open interest through the session — a level being defended will keep adding open interest, while a level about to break usually sheds it.

Change in open interest shows what is happening today, while standing open interest shows what was already there. A strike can hold a very large position built up over weeks yet see no fresh activity, and another can be quiet in absolute terms but adding aggressively right now. Reading both together separates old positioning from live intent.

Volume counts every contract traded during the session and resets to zero the next day, while open interest counts contracts still outstanding and carries forward until they are closed or expire. High volume with rising open interest points to fresh positioning; high volume with falling open interest points to existing positions being unwound.

Implied volatility is set by supply and demand for each contract separately, so the same strike can price its call and its put differently. Persistent gaps usually reflect directional demand — heavier put buying lifts put implied volatility, producing the downside skew commonly seen in index options. Watching the gap widen or narrow is itself a read on positioning.

Open interest is the total number of option contracts in a strike that are still open and not yet squared off or settled. It counts positions, not trades. Rising open interest means fresh contracts are being created and new money is entering that strike; falling open interest means existing positions are being closed out.

Look for the strikes carrying the largest put and call open interest around the current spot. The heaviest put strike below spot is commonly treated as a support reference and the heaviest call strike above spot as resistance. Then watch change in open interest through the session — a level being defended will keep adding open interest, while a level about to break usually sheds it.

Change in open interest shows what is happening today, while standing open interest shows what was already there. A strike can hold a very large position built up over weeks yet see no fresh activity, and another can be quiet in absolute terms but adding aggressively right now. Reading both together separates old positioning from live intent.

Volume counts every contract traded during the session and resets to zero the next day, while open interest counts contracts still outstanding and carries forward until they are closed or expire. High volume with rising open interest points to fresh positioning; high volume with falling open interest points to existing positions being unwound.

Implied volatility is set by supply and demand for each contract separately, so the same strike can price its call and its put differently. Persistent gaps usually reflect directional demand — heavier put buying lifts put implied volatility, producing the downside skew commonly seen in index options. Watching the gap widen or narrow is itself a read on positioning.

Gamma exposure is an estimate of how much of the underlying option writers would need to buy or sell to stay hedged as price moves. It multiplies each strike's gamma by the open interest sitting there, scaled so the answer reads as rupees per one per cent move. A large total means hedging flow is large relative to the move that triggers it.

The gamma flip, also called the zero-gamma level, is the price at which the measured net gamma exposure would change sign. Above it the book is measured as net positive and hedging leans against each move; below it the book is net negative and hedging leans with it. This page finds it by recomputing gamma at candidate levels rather than by interpolating the strike profile, because the two methods can disagree by thousands of points on the same tape.

The call gamma wall is the strike above spot carrying the most call-side gamma, and the put gamma wall the strike below spot carrying the most put-side gamma. They are weighted by gamma rather than by contracts, so they can sit on a different strike from the heaviest open-interest strike shown on the Open Interest page — gamma decays with distance from spot, and the two measures answer different questions.

It is weaker here than the American research it comes from. That work assumes dealers are long calls and short puts, which follows from United States customers buying protective puts and writing calls. Indian participant data does not show a stable book of that shape, and index options here are cash settled with heavy expiry-day volume. The absolute gamma reading, which does not assume who holds what, is the part that survives if the convention does not hold.

Open interest and traded premium come from the same session snapshots the rest of this site uses. Gamma is not taken from the feed: it is recomputed per strike from a volatility solved off the traded price, because a strike's call and put must share one gamma and vendor-reported values here do not always agree. Readings are suppressed rather than estimated once a series has settled.

Quotes stream live from the exchange feed during market hours through a WebSocket connection, so open interest, premium and Greeks update continuously rather than on a fixed refresh. If the live feed goes quiet the terminal falls back to periodic snapshot polling automatically. Outside market hours the last completed session is shown.

Implied volatility is the annualised movement that an option's traded price implies, once strike, time to expiry and the underlying's level are accounted for. It is not a forecast of direction. A higher reading means the market is paying more for the same expected range; a lower one means it is paying less. It is quoted as a percentage a year, which is why it needs converting before it means anything over a few days.

It is the reading at the centre of the option chain, where the strike matches where the market prices the underlying at expiry. That centre is the forward, not the current spot price, and the two differ by the cost of carry — enough to sit a couple of strikes apart on a monthly expiry. Using the forward keeps the figure comparable from one session and one expiry to the next.

Because with the correct centre they should. Put-call parity is an arbitrage relationship, not a model, and it means one volatility reprices both legs of a strike. Where an exchange or broker shows two different figures at the same strike, the difference measures bid-ask friction and stale quotes on the less liquid leg. This page shows that difference separately, as a data-quality reading rather than as a signal.

Multiply the underlying's level by the volatility and by the square root of the time to expiry in years. This page does that for you and prints the result as the expected move. It is a one-standard-deviation figure, so roughly two sessions in three finish inside it and one does not — and the arithmetic says nothing at all about which side of the range that move lands on.

Both compare today's reading against about a year of daily closes, and this site keeps intraday session history rather than years of it. A rank computed from a few weeks would be a different statistic wearing the same name: it depends on the highest and lowest readings in its window, so a short window overstates it and a single quiet spell can move it dramatically without today's reading changing at all.

Implied volatility is the annualised movement the option market is currently pricing into a contract, derived by working the Black-Scholes formula backwards from the traded premium. It is an expectation, not a measurement of past movement. When implied volatility rises, premium expands for the same spot price; when it falls, premium contracts.

Open interest is the total number of option contracts in a strike that are still open and not yet squared off or settled. It counts positions, not trades. Rising open interest means fresh contracts are being created and new money is entering that strike; falling open interest means existing positions are being closed out.

Look for the strikes carrying the largest put and call open interest around the current spot. The heaviest put strike below spot is commonly treated as a support reference and the heaviest call strike above spot as resistance. Then watch change in open interest through the session — a level being defended will keep adding open interest, while a level about to break usually sheds it.

Change in open interest shows what is happening today, while standing open interest shows what was already there. A strike can hold a very large position built up over weeks yet see no fresh activity, and another can be quiet in absolute terms but adding aggressively right now. Reading both together separates old positioning from live intent.

Volume counts every contract traded during the session and resets to zero the next day, while open interest counts contracts still outstanding and carries forward until they are closed or expire. High volume with rising open interest points to fresh positioning; high volume with falling open interest points to existing positions being unwound.

Implied volatility is set by supply and demand for each contract separately, so the same strike can price its call and its put differently. Persistent gaps usually reflect directional demand — heavier put buying lifts put implied volatility, producing the downside skew commonly seen in index options. Watching the gap widen or narrow is itself a read on positioning.

Dozens on either side of spot — a full chain including the wings commonly runs past eighty rows in total. The exchange lists strikes on a grid and extends it outward as the index travels, so the count grows on a trending day. What matters more than the count is that open interest is spread across most of those rows rather than clustered in a handful near the money.

Near-the-money strikes are listed about 50 points apart, which is roughly 0.20% of the index at current levels. The exchange sets that grid and extends it as spot moves, and spacing is generally wider on strikes far from the money. Treat it as the grid you can see on the chain today rather than a permanent property of the contract.

No — they are cash-settled. Nothing is delivered and no stock position appears in your account. At expiry the contract pays a rupee difference computed against the settlement value the exchange publishes for the expiry day it has set. That also means no assignment risk in the equity sense, and no repricing from any single constituent's corporate action.

Because the participant base behind it is broader. Index option flow in India concentrates on this contract, portfolio hedging naturally reaches for strikes some distance from spot, and systematic premium-selling programmes populate the wings continuously. None of those activities needs a directional view, so open interest persists at far strikes instead of draining away between events.

It is commonly read that way, and it is a crowding observation rather than a rule. Heavy call open interest marks where writers have positioned, not a level price must respect — those levels break regularly, and often precisely because everyone was watching them. Open interest also counts contracts rather than opinions, so hedging can build the same number.

Both, and preferably side by side. The near-dated series carries most of the day's volume and reacts fastest to spot, so it describes intraday tone. The monthly carries a much larger standing base built over weeks and describes positional context. Reading one alone makes an ordinary roll between series look like positions being abandoned.

Two separate reasons stack on top of each other. The index trades above twice NIFTY's level, so any percentage move is worth more than twice as many points, and points are what premium is quoted in. On top of that, a concentrated banking index prices a somewhat wider percentage move — around 1.15% against roughly 0.90%. Only the percentage figure is comparable.

Wider than the roughly 50-point grid used near the money on NIFTY, because 50 points on an index near 55,000 would be under a tenth of a per cent and would produce an unreadable chain. The exchange sets the grid and extends it outward as spot travels. In percentage terms the two grids are close; in points, each BANKNIFTY step is a far larger gap.

Because it holds far fewer names and every one of them is a bank. They share a rate cycle, a credit cycle, a regulator and a deposit market, so news touching the sector touches every constituent in the same direction at once. A fifty-stock benchmark spread across sectors dilutes the same news across companies that are moving independently.

At the money, yes — it is one of the most heavily traded index option contracts on the exchange. The difference appears once you walk away from spot. Open interest and two-sided quotes thin out faster on the wings than on a broad index, so a far strike's printed last-traded price may not be a price you can actually transact at.

Not usefully. PCR has no absolute scale and no shared neutral point across underlyings, because each one carries its own mix of hedgers and speculators. Compare a reading against that instrument's own recent range instead, and treat the direction of travel within the range as the observation rather than the level itself.

No. A larger premium is the market's price for a wider expected move, and both sides transact at a price that already reflects it. What scales with the index level is the size of every number involved — the premium, the daily decay in rupees, and the loss an adverse move produces. None of that is an edge for the buyer or for the writer.

SENSEX options are listed, matched and cleared on BSE, not NSE. It is the only major index option contract in this set that sits on the other exchange. Its open interest is a separate pool built by BSE participants, and its expiry calendar is set by BSE independently of the NSE one.

Because premium scales with the level of the underlying, and SENSEX trades at more than three times NIFTY. An 800-point SENSEX straddle on an 80,200 index and a 245-point NIFTY straddle on a 24,500 index are both 1.00% of spot. The rupee figures differ by 3.3 times. What they price is identical.

Near the money the exchange lists SENSEX strikes in hundred-point steps, against fifty points on NIFTY, and it extends and widens that grid as spot travels. Against the index level, though, a hundred points on 80,200 is 0.12% while fifty on 24,500 is 0.20% — the SENSEX grid is the finer of the two.

No. BSE derivatives volume is smaller than NSE volume, so the SENSEX book is thinner, particularly away from the money. Near-the-money rows quote tightly. Further out, spreads widen faster, a single large position can visibly move strike-level open interest, and distant strikes can carry stale last-traded prices.

Not directly. The exchanges set different contract sizes and revise them, so one contract on each board is a different quantity of index exposure, and the two books have different participants. Compare the shape of the distribution instead — which strikes are heaviest and how fast it falls away — because shape is scale-free.

Because every points-based number on a chain scales with the index it is written on. Strike spacing, premium, spreads, decay and distance to a wall are all larger on a higher index without meaning anything different. Dividing by spot removes the level and leaves what the board is actually pricing.

FINNIFTY is an NSE index of financial services companies, weighted by capped free float. It holds banks alongside insurers, non-bank lenders, housing finance companies and asset managers. That makes it a single-sector index — broader than a banks-only index, and far narrower than the whole-market benchmark it sits inside.

BANKNIFTY holds banks and nothing else, while FINNIFTY adds the rest of financial services — insurers, NBFCs, housing finance and asset managers. The two share their largest constituents, so they agree most of the time. They separate when the non-bank half moves on its own, and that gap is the useful signal.

Fewer participants trade it. It is a sector contract competing for attention with the benchmark and with a banking index that many traders already use as their volatility expression. The result is less open interest at each strike, wider spreads away from the money, and distant strikes that can go untraded for long stretches.

Treat it more cautiously than the same picture on a deeper book. Heavy call open interest above spot is a crowding observation on any underlying, and here the crowd may be small. Check how it accumulated: gradual build with volume beside it is worth more than a single large print far from spot.

The spread is the gap between the highest price a buyer is bidding and the lowest a seller is asking. It is the immediate cost of entering and exiting. A wide spread also makes the mid-price misleading, because no trade happens there — on thin strikes the mid is arithmetic rather than an available price.

It marks where positioning is concentrated, and those strikes often behave as reference levels — heavy calls above spot are commonly read as resistance, heavy puts below as support. This is a crowding observation, not a rule. Levels break, usually when that open interest unwinds quickly.