How do you read an option chain?
An option chain lists the contracts available on one stock, organised by expiry and strike; many, such as Moomoo's, put calls on the left and puts on the right 1. Each row is one strike; for each option it shows the bid and the ask, often with volume, open interest and the last price 1. A market order to buy generally fills at or near the ask, and one to sell at or near the bid 2; one contract covers 100 shares of the quoted price 3.
A made-up chain for a $50 stock at 30% implied volatility: model prices, with a made-up spread of about 3% each side, at least a cent. Choose an expiry and read across a row.
Down the table
By the formula, a call with a higher strike costs less and a put with a higher strike costs more 4: watch the columns. In this chain a longer expiry costs more on both sides 4. The row at the stock's price is at the money 5.
The two prices in each cell
Buying at the ask and selling straight back at the bid loses the gap between them: in the made-up chain above, the 30-day $50 call is asked at $1.86 and bid at $1.74, so $0.12 a share is gone at once. A wide gap on a cheap option can be a large share of its price.
What this shows, and what it doesn't
A made-up chain from the formula, not market quotes. A real chain shows volume and open interest too 1, and real spreads differ from one option to the next.
Go further
Sources (5), checked 20 October 2026 and 27 October 2026
- Moomoo, “Options Chains: Definition, How to Read and Analyze Them”. Read it (read 27 October 2026)
- US Securities and Exchange Commission, Investor.gov, “Types of Orders”. Read it (read 20 October 2026)
- The Options Clearing Corporation, “Primer: Equity (stock and ETF) Options”. Read it (read 27 October 2026)
- Fischer Black and Myron Scholes, “The Pricing of Options and Corporate Liabilities”, Journal of Political Economy 81(3), 637–654, 1973. Read it (read 20 October 2026)
- CME Group, “Calculating Options Moneyness & Intrinsic Value” (Introduction to Options course). Read it (read 27 October 2026)
Now try it on a scenario of your own
Pick where a simulated stock might be, and by when: drag one dot and see, side by side, what buying shares, one option, or a pair of options (a call or put spread) would each do. Free, no sign-up.
Check a trade before you make it →