An options chain is a grid: rows are strike prices, columns are calls and puts, and each cell shows bid, ask, volume, open interest, and IV for that contract. The visual density scares beginners. It should not.
The five columns that matter on day one: strike (the contract's anchor price), bid (what buyers are paying right now), ask (what sellers are demanding), mid (the midpoint between bid and ask, your honest entry estimate), and delta (the contract's directional sensitivity). Volume and open interest matter for liquidity — wide bid-ask spreads on illiquid contracts will eat your edge before you ever experience the strategy's math.
Practical rule: if the bid-ask spread is wider than 5% of the option's mid price, the contract is too illiquid for active trading. Stick to weeklies and monthlies on the major indexes (SPY, QQQ, IWM) and the most-traded large-caps until you have a feel for what tight markets look like. Liquidity is invisible until it isn't, and slippage on a wide chain can cost more than the strategy's edge.
Frequently Asked Questions
What's a normal bid-ask spread on a liquid option?
A penny to a few cents on weekly SPY options. Less than 5% of mid price on most large-cap monthlies. Anything wider should be approached carefully.
Should I always trade at the mid price?
Start by quoting the mid. If unfilled after a minute, walk one penny toward the ask (when buying) or the bid (when selling). Never market-order an option.