simple rest api with so much accuracy and custom calculated field that help for 0dte trade

What stands out most to me is the breadth and transparency of the data. Most services give you GEX and stop there, but FlashAlpha publishes the full Greek exposure picture (gamma, vanna, charm, delta), along with pin scores, magnet strikes, expected move bounds, IV term structure, and per-strike data, plus their 4-quadrant regime framework. They also show the raw numbers with straightforward, factual descriptions instead of hiding behind black-box “signals,” which is exactly what I need to build my own systematic workflow around. The 0DTE data is especially strong. Pin score, gamma acceleration, and the IV 0DTE/7DTE ratio let me see in real time whether a session is pinning, breaking out, or simply priced for an event.