- 0DTE
- An option expiring the same day it trades. SPY, QQQ, IWM and SPX list them every session. With no time left, the price is almost pure gamma and moves violently against small moves in the underlying.
SPX 0DTE Cheat Tool
- Assignment
- What happens to the seller of an option when the buyer exercises. The seller must deliver shares on a call or buy them on a put. Assignment can occur at any time on American-style contracts, though it is far more likely once the option is deep in the money or near expiration.
- At the Money (ATM)
- The strike sitting at or nearest the current stock price. At-the-money options carry the most time value and the most gamma, so they react fastest to a move.
- Bid-Ask Spread
- The gap between the highest price a buyer will pay and the lowest price a seller will take. You buy at the ask and sell at the bid, which is why a position shows a loss the instant it opens, before the stock has moved.
- Breakeven
- The stock price at expiration where a position makes nothing and loses nothing. A long call breaks even at the strike plus the premium paid.
- Butterfly
- A three-strike position: buy 1, sell 2 at a middle strike, buy 1 further out. It costs a fixed debit, pays the most if the stock lands at the middle strike, and the two outer legs (the wings) cap the loss.
Butterfly Cheat Tool
- Call
- An option giving the holder the right to buy 100 shares at the strike price on or before expiration. Buying one is a bet the stock rises. Selling one takes in premium and carries the obligation to deliver shares.
- Cash Settled
- An option that pays out in cash at expiration rather than delivering shares. SPX options are cash settled and European style, so they cannot be exercised early. SPY options deliver shares and can be exercised early.
- Credit
- Money collected when a position opens because the options sold cost more than the options bought. A credit is the most the position can make.
- Danger Breakeven
- In a front-ratio spread, the price beyond max profit where the extra short contracts overwhelm the single long one and the trade turns into a loss. Past this level the exposure keeps growing, so it is the number used for position sizing.
Short Ratio Spreads
- Days to Expiration (DTE)
- Calendar days left until an option expires. Time value decays faster as DTE falls, and the last 2 weeks carry most of that decay.
- Debit
- Money paid to open a position because the options bought cost more than the options sold. On a defined-risk position the debit is the most that can be lost.
- Delta
- How much an option's price moves for a $1 move in the stock. It also reads roughly as the chance the option ends in the money: a 30-delta call is priced near a 30% chance of finishing past the strike.
- Exercise
- Using an option's right to buy shares (call) or sell them (put) at the strike. Most traders close the option instead because exercising gives up remaining time value.
- Expiration
- The date an option stops trading and settles. Whatever intrinsic value it holds at that moment is all it is worth. Everything else has decayed to zero.
- Extrinsic Value
- The part of an option's price above its intrinsic value, made up of time left and implied volatility. It goes to zero at expiration. That is what an option seller collects and an option buyer pays for.
- Floor Trade
- An options order worked by a human broker on the exchange floor instead of routing electronically. These prints are mostly institutional and tend to come in size, which is why they are tracked separately.
Options Floor Trades
- Gamma
- How fast delta changes as the stock moves. Gamma is highest at the money and highest near expiration. It is why a 0DTE position can go from nearly worthless to deep in the money on a small move.
- Gamma Exposure (GEX)
- An estimate of how much stock market makers must buy or sell to stay hedged as price moves. Positive dealer gamma means they sell into strength and buy into weakness, dampening moves. Negative gamma means they do the opposite, amplifying moves.
Gamma Exposure
- Gamma Wall
- A strike carrying enough dealer gamma to act like a magnet or a brake on price. Large call walls tend to sit above spot and cap rallies. Large put walls tend to sit below and slow declines.
Gamma Exposure
- Implied Move
- The size of the move the option chain is pricing in through a given expiration, backed out of at-the-money premium. It is what the market is charging for the move and the bar a real move has to clear for a long option to pay.
- In the Money (ITM)
- A call with a strike below the stock price, or a put with a strike above it. An in-the-money option carries intrinsic value, so part of its price is already real.
- Intrinsic Value
- What an option would be worth if it expired right now: the distance the strike sits in the money, and zero otherwise.
- Max Profit
- The most a defined position can make and the price where it makes it. On a butterfly that is the middle strike. On a credit spread it is anywhere past the short strike.
- Net Credit
- What remains after the long and short legs of a spread net out when the shorts bring in more than the longs cost. It is cash in the account on day one and the ceiling on the trade's profit.
- Open Interest (OI)
- The number of contracts currently held open at a strike. Volume measures what traded today. Open interest measures what is still on the books from prior sessions.
- Out of the Money (OTM)
- A call with a strike above the stock price, or a put with a strike below it. It holds no intrinsic value, so the entire price is time and volatility.
- Premium
- The price of an option, quoted per share. A contract covers 100 shares, so a premium of 2.50 costs $250.
- Probability of Profit (POP)
- The chance a position is worth at least a dollar at expiration. Selling further out of the money raises POP and lowers the credit, so the two always trade against each other.
Options Seller Cheat Tool
- Put
- An option giving the holder the right to sell 100 shares at the strike price on or before expiration. Buying one is a bet the stock falls or insurance on shares already owned.
- Return on Buying Power
- Premium collected divided by the buying power the trade ties up. It lets a small credit on a tight spread be compared against a large credit on a wide one, because the second uses far more of the account.
Return on Buying Power Calculator
- Rho
- How much an option's price moves per 1 percentage point change in interest rates. It is the smallest of the Greeks on short-dated contracts and only starts to matter on long-dated ones.
- Roll
- Closing an option and reopening the same structure at a later expiration, a different strike, or both. On this site a roll's debit is measured as the cost of buying back the old leg alone, so the new leg's credit is never netted into it.
- Short Ratio Spread
- Buy 1 option and sell 2 or 3 further out of the money, usually for a credit. Max profit sits at the short strike. Past the danger breakeven the extra short contracts leave open risk.
Short Ratio Spreads
- Strike
- The price at which an option can be exercised. It is fixed for the life of the contract, so every option on a ticker is a bet about where price sits against one specific number.
- Sweep
- An order broken across several exchanges at once to fill immediately rather than wait for a better price. Paying up for speed usually signals urgency behind the order.
- Theta
- The dollar value an option loses per day from time passing alone, with the stock unchanged. It is what a seller collects and a buyer fights. It accelerates as expiration approaches.
Options Buyer Cheat Sheet
- Vega
- How much an option's price moves per 1 point change in implied volatility. A long option gains on rising IV even if the stock stands still and loses on falling IV the same way.
- Volume / OI Ratio
- Contracts traded today divided by the open interest already sitting at that strike. Above 1 means today's activity is larger than everything on the books there, so the position is most likely new rather than a close-out.
Options Screener