Option chain
Reading the option chain: every expiration on one line, and the quotes, greeks, volume, and open interest of the ones you open.
The option chain (/SPX/chain) lists every expiration of the ticker, one line each. A line shows the date (with Weekly, Monthly, or Quarterly where it is one), the days left, the expected move in points and as a share of spot, the at-the-money IV, the session's volume, the open interest, and the put/call ratios by volume and by open interest. Read down the lines and you have the term structure.
Press a line, or Tab to it and press Enter, to open that expiration's chain under it: calls on the left, the strike in the middle, puts on the right. The nearest starts open, and any number can be open at once, so today's and Friday's can sit one above the other. An open expiration shows about 13 strikes around spot and scrolls inside its box through every strike; its foot names the at-the-money strike and how many strikes it lists. The open expirations are in the page's address, so a link you share opens the same ones.
Reading the chain
Each side shows Bid, Ask, Last, Δ (delta), Vol (contracts traded this session), and OI (open interest). The Columns menu adds Mid, Spread % (the bid-ask spread as a share of the mid), IV (implied volatility), Γ (gamma), Θ (theta, per share per day), and vega (per volatility point, per share). Your columns are kept in this browser.
- The at-the-money strike, the one nearest spot, is boxed in indigo.
- In-the-money cells are shaded: calls below spot, puts above.
- A line between two strikes marks spot, labelled with the price.
- A last price from an earlier session is dimmed. Volume counts this session only, so before the first trade of the day every contract shows 0.
- A dash means no value: no quote, or no IV to compute greeks from.
An expiration's volume, open interest, and put/call ratios on its line cover every strike it lists.
On a narrow screen both sides stay, with fewer columns: Bid and Ask each side of the strike on a phone, then Δ, OI, Last, and Vol as the width allows. Columns you add from the menu scroll sideways under the strike, which stays in place.
Credit spreads
Credit spreads are built in the strategy calculator: pick Bull Put Spread or Bear Call Spread in its library and it puts the short strike at the edge of the expected move (or at the delta you choose) on the expiration you pick, with the credit, max loss, breakeven, and return on risk for the position. A bull put spread sells a put and buys a lower one; a bear call spread sells a call and buys a higher one. Older links to the chain's Bull put and Bear call tabs open the strategy calculator on that spread.
Open in other tools
Pressing a contract opens a small menu: History (that contract's trades; see contract stats), Strategy calculator (the contract as a position you can edit), and on Pro Wheel and income. When only one of those is open to you, the press goes straight there.
On each plan
Signed out, SPX, SPY, QQQ, and IWM show every expiration's line at the last close; opening one takes a free account. Free shows every line for those four and opens expirations up to 45 days out; a later one shows its line with a lock. Pro opens any ticker and every expiration, and the lines and open expirations update with each new snapshot. The chain can also sit on the overview as an added panel, at the top bar's expiration; its maximize opens this page with that expiration open.