New to gamma exposure? What Is GEX? covers the formula, dealer hedging mechanics, and how to read gamma flip levels. Also see: GEX Trading Guide for practical trading strategies using this data.

Works with CME index futures. Pass ES=F or NQ=F and URL-encode the = as %3D - e.g. /v1/exposure/gex/ES%3DF. Options-on-futures are priced with Black-76 using the CME multiplier ($50/pt ES, $20/pt NQ); CME index futures are Growth-tier. See the futures hub.

Endpoint

GET /v1/exposure/gex/{symbol}

Auth required (X-Api-Key) Rate Limited: Yes

Parameters

Name	In	Required	Default	Description
`symbol`	path	yes	-	Underlying symbol
`expiration`	query	no	`all`	Filter to single expiry (`yyyy-MM-dd`)
`min_oi`	query	no	`0`	Minimum open interest threshold

Note: Full-chain GEX (all expirations) requires the Growth plan. Add ?expiration=yyyy-MM-dd to filter by a single expiry on lower plans.

curl -H "X-Api-Key: YOUR_API_KEY" \
  "https://lab.flashalpha.com/v1/exposure/gex/SPY"

import requests

resp = requests.get(
    "https://lab.flashalpha.com/v1/exposure/gex/SPY",
    headers={"X-Api-Key": "YOUR_API_KEY"}
)
data = resp.json()
print(f"Net GEX: ${data['net_gex']:,.0f}")
print(f"Gamma Flip: {data['gamma_flip']}")

const resp = await fetch(
  "https://lab.flashalpha.com/v1/exposure/gex/SPY",
  { headers: { "X-Api-Key": "YOUR_API_KEY" } }
);
const data = await resp.json();
console.log(`Net GEX: $${data.net_gex.toLocaleString()}`);
console.log(`Gamma Flip: ${data.gamma_flip}`);

API Key

Response

{
  "symbol": "SPY",
  "underlying_price": 597.505,
  "as_of": "2026-02-28T16:30:45Z",
  "gamma_flip": 595.25,
  "net_gex": 2850000000,
  "net_gex_label": "positive",
  "strikes": [
    {
      "strike": 575.0,
      "call_gex": 12500000,
      "put_gex": 8900000,
      "net_gex": 21400000,
      "call_oi": 15000,
      "put_oi": 12000,
      "call_volume": 250,
      "put_volume": 180,
      "call_oi_change": 500,
      "put_oi_change": -200
    }
  ]
}

Key Response Fields

Field	Type	Description
`symbol`	string	Underlying symbol
`underlying_price`	number	Current price of underlying
`as_of`	string	ISO 8601 timestamp
`gamma_flip`	number	Strike where net GEX crosses zero - the gamma flip point
`net_gex`	number	Aggregate net gamma exposure in dollars
`net_gex_label`	string	Gamma regime label (`positive` or `negative`)
`strikes`	array	Per-strike breakdown
`strikes[].strike`	number	Strike price
`strikes[].call_gex`	number	Call gamma exposure at this strike
`strikes[].put_gex`	number	Put gamma exposure at this strike
`strikes[].net_gex`	number	Net (call + put) gamma exposure
`strikes[].call_oi`	number	Call open interest
`strikes[].put_oi`	number	Put open interest
`strikes[].call_volume`	number	Call volume
`strikes[].put_volume`	number	Put volume
`strikes[].call_oi_change`	number	Day-over-day call open interest change
`strikes[].put_oi_change`	number	Day-over-day put open interest change

Errors

Status	Description
`400`	Invalid expiration format
`403`	Full-chain GEX requires Growth plan
`404`	Symbol not found or no data

Plans & Rate Limits

Plan	Rate Limit	Access
Free	5 requests/day	Stock quotes, GEX & key levels (single expiry), tickers, options meta, symbols, surface - individual US equities only
Basic	100 requests/day	Everything in Free + ETFs & index symbols (SPY, QQQ, SPX, VIX...) + DEX/VEX/CHEX exposure + max pain + Market Overview
Growth	2,500 requests/day	+ Summary, narrative, history, option quotes, full-chain GEX (no expiry filter)
Alpha	Unlimited	Full access + advanced volatility analytics

What Is Gamma Exposure?

Gamma exposure (GEX) measures the dollar amount of shares that options dealers must buy or sell to delta-hedge for every 1% move in the underlying price. When dealers are long gamma (positive GEX), they buy dips and sell rallies - dampening volatility and creating mean-reverting, range-bound markets. When dealers are short gamma (negative GEX), their hedging amplifies moves - leading to trending, volatile price action. The gamma flip point marks where net exposure switches sign, often acting as a key pivot level.

Common Use Cases

Locate the gamma flip - the gamma_flip spot where net dealer gamma crosses zero and the volatility regime changes; fade extensions above it, respect momentum below
Map dealer walls - the largest positive-GEX strikes act as magnets and intraday support/resistance that absorb price moves
Read the regime from net_gex - positive means dampened and range-bound, negative means amplified and trending; gate strategy selection on the sign
Anticipate expiration pinning - heavy GEX concentration at an ATM strike into expiry pins price; confirm against max pain and pin risk
Size and stop with GEX magnitude - larger absolute net GEX implies tighter dealer hedging and smaller realized ranges; calibrate stop distances accordingly
Track the flip intraday - watch the flip migrate versus spot to catch the moment dealers switch from dampening to amplifying moves

Complementary endpoints

Delta Exposure (DEX) - directional dealer positioning alongside gamma
Vanna Exposure (VEX) - how dealer gamma shifts as implied vol moves
Charm Exposure (CHEX) - how positioning decays as expiry approaches
Key Levels - gamma flip, call wall, put wall, and max pain in one call

Gamma Exposure (GEX) API