Works with CME index futures. Pass ES=F or NQ=F and URL-encode the = as %3D - e.g. /v1/exposure/dex/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/dex/{symbol}

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

Parameters

Name	In	Required	Default	Description
`symbol`	path	yes	-	Underlying symbol
`expiration`	query	no	`all`	Filter by expiry date `yyyy-MM-dd`, or `0dte` for same-day only

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

import requests

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

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

API Key

Response

{
  "symbol": "SPY",
  "underlying_price": 597.505,
  "as_of": "2026-02-28T16:30:45Z",
  "net_dex": -450000000,
  "strikes": [
    {
      "strike": 575.0,
      "call_dex": 5600000,
      "put_dex": 4200000,
      "net_dex": 9800000
    }
  ]
}

Key Response Fields

Field	Type	Description
`symbol`	string	Underlying symbol
`underlying_price`	number	Current price of underlying
`as_of`	string	ISO 8601 timestamp
`net_dex`	number	Aggregate net delta exposure in dollars
`strikes`	array	Per-strike breakdown
`strikes[].strike`	number	Strike price
`strikes[].call_dex`	number	Call delta exposure at this strike
`strikes[].put_dex`	number	Put delta exposure at this strike
`strikes[].net_dex`	number	Net (call + put) delta exposure

What Is Delta Exposure?

Delta exposure (DEX) measures the net directional position that options dealers hold. When net DEX is positive, dealers are net long delta - they've accumulated shares as hedges. When net DEX is negative, dealers are short the underlying. Unlike GEX (which measures hedging acceleration), DEX captures the absolute directional tilt. Large shifts in DEX can precede directional moves, as dealer hedging activity feeds back into the underlying's supply and demand.

Common Use Cases

Read the directional tilt from net_dex - positive means dealers are net long (call-heavy positioning), negative means net short (put-heavy); set your directional bias from the sign
Flag stretched positioning - extreme net_dex readings mark crowded directional bets that can unwind into mean-reversion; fade the extreme
Pinpoint the heaviest strikes - scan strikes[].net_dex to see where directional conviction concentrates and which levels dealer hedging will defend
Compare DEX across symbols - rank net_dex across a watchlist to spot sector rotation and where conviction is building
Track event buildup - watch net_dex accumulate into earnings or FOMC to see which way the market is leaning before the print
Separate direction from volatility - pair net_dex with GEX so you know whether a regime is about directional tilt or hedging acceleration, then choose the strategy accordingly

Complementary endpoints

Gamma Exposure (GEX) - hedging acceleration to pair with directional tilt
Vanna Exposure (VEX) - how dealer delta shifts as implied vol moves
Charm Exposure (CHEX) - how dealer delta drifts as expiry approaches
Live Flow DEX - intraday DEX driven by real-time order flow

Delta Exposure (DEX) API