Up or down is the first thing to sort out with options. A call is the right to profit when the market goes up; a put is the right to profit when it goes down. On one option chain, calls sit on the left, puts on the right, with the strike price in the middle; which side you buy decides which direction you want the market to move.
A 0DTE contract expires the same day — there is no "wait a few days." The buyer needs the move to happen within hours, enough to cover the premium and fees. As expiry approaches, the time value in the contract shrinks; at expiry, a contract that has not reached its strike expires worthless. For the buyer, the direction must move far enough the same day; for the seller, if the direction never reaches the strike, the premium collected stays. That is how the expiry mechanics work — not a promise of returns.
On the order ticket, first pick Call or Put, then buy or sell. Before placing the order, check the mid price and the bid-ask spread — you can skip a strike whose spread looks too wide. When you are starting out, try one long single-leg contract first: see clearly how much it can lose and gain, then try selling and spreads. Write your exit plan before you open the trade too — how much profit to take, how much loss to accept, and the latest time to leave — all three before entry, not after.
This simulator uses real CBOE option chains delayed about 15 minutes, starts with $10,000 in virtual funds, charges $0.65 per contract per side in fees, and shows P&L net of fees; short-sale margin is a simplified simulated rule at 20% of the strike, not a real broker margin. The simulator is for practicing orders, discipline, and review. It is not investment advice and promises no returns.
Back to the simulator | What is 0DTE? | Simulator Discipline | FAQ | How to Read the Option Chain | Expiry Day | Selling Margin | End-of-Day Review | What is SPX? | SPX vs SPY Options: What Is the Difference? | In, At, or Out of the Money | Implied Volatility | How to Write an Exit Plan