0DTE Options Decoded

Understand the contract. Make the risk visible.

Same-day options compress decisions into hours-and sometimes minutes. Before choosing a strike or entering a spread, you need to understand what you own, what you paid, and how quickly its value can change.

0DTE Options Decoded: A Practical Guide to SPX Trading, the Greeks, and Machine Intelligence takes beginning and intermediate readers from the everyday meaning of calls and puts to the interaction of price, time, volatility, and risk. SPX is the focus, with SPY providing wider market context.

Clear explanations, original diagrams, and worked examples connect the numbers on an options screen to the money at risk.

Inside, you'll learn how to:

• Read strikes, premiums, intrinsic value, and extrinsic value.
• Understand buying versus selling options, defined-risk structures, and the risks of uncovered positions.
• Interpret delta, gamma, theta, and vega as expiration approaches.
• Compare single options, spreads, iron condors, and butterflies.
• Understand SPX exercise and cash settlement.
• Examine price structure, expected ranges, premium behavior, and gamma estimates.
• Assess backtests and machine-learning claims with attention to assumptions, missing information, and uncertainty.

Put the concepts into context with the companion dashboard.

The companion website includes a video walkthrough and an interactive browser sample featuring an SPX session map, premium analytics, a Gamma/OI ladder, an option-chain explorer, and an editable expiration-payoff laboratory. The sample uses clearly labeled synthetic data, allowing you to explore the tools without a market-data subscription or brokerage connection.

Reinforce your understanding with 98 practice questions, with answers collected separately in a final appendix.

Written by Harmohit Lyall, this book emphasizes a considered decision process: understand the exposure, identify the evidence, define the risk, and recognize what remains unknown.

Educational material only. Options involve substantial risk. Experimental models and historical findings do not establish or guarantee future trading performance.