# NDX — Overview · GammaGrid demo

**Gamma weather: Storm.** This chain has no gamma flip within 25% of the price, so only the sign of gamma is known — negative, hedging amplifies moves. *(next 30 days · 22 expiries)*

| Level | Value |
|---|---|
| Price | 27,817.15 |
| Call wall | 29,675.00 |
| Put wall | 20,000.00 |
| Gamma flip | — |
| Net GEX | -1.6 M |

## Put/call ratio

At the latest collection: by volume **0.99**, by open interest **1.16**. The page draws the ratio over 365 days and the implied-volatility surface.

## About these numbers

Computed by GammaGrid from the NDX options chain — dealer gamma exposure, max pain and the walls are GammaGrid's own arithmetic over open interest; the source data is delayed. Collected 2026-11-09T17:01:32.783522 UTC; this page follows the collection, roughly every fifteen minutes while the market is open.

Other views of NDX: [Max Pain / GEX](https://app.gammagrid.io/demo/t/NDX/max-pain.md) · [GEX Heatmap](https://app.gammagrid.io/demo/t/NDX/heatmap.md) · [Volatility (IV)](https://app.gammagrid.io/demo/t/NDX/volatility.md).

Canonical page: <https://app.gammagrid.io/demo/t/NDX> · The demo shows the free list only; a GammaGrid account watches any US-listed ticker with options, replays earlier collections and opens every contract: <https://app.gammagrid.io/>