ALPHA TIER
HISTORICAL
Historical DEX Data API
Query delta exposure by strike at any minute since April 2018. Same response shape as the live /v1/exposure/dex endpoint — add at= to replay dealer delta-hedging pressure from any historical moment.
Coverage
2018-04-16 → 2026-04-02
Granularity
1 minute
Tier
Alpha+
Format
JSON (REST)
Endpoint
Host:
historical.flashalpha.com
Auth: X-Api-Key
Tier: Alpha
| Name | In | Required | Default | Description |
|---|---|---|---|---|
symbol | path | yes | — | Underlying symbol |
at | query | yes | — | As-of timestamp (yyyy-MM-ddTHH:mm:ss ET) |
expiration | query | no | all | Filter to a single expiry (yyyy-MM-dd) |
curl -H "X-Api-Key: YOUR_API_KEY" \
"https://historical.flashalpha.com/v1/exposure/dex/SPY?at=2020-03-16T15:30:00"
Response
{
"symbol": "SPY",
"underlying_price": 246.01,
"as_of": "2020-03-16T15:30:00",
"as_of_requested": "2020-03-16T15:30:00",
"payload": {
"net_dex": -169419489077,
"strikes": [
{ "strike": 240, "call_dex": 612481.33, "put_dex": -290214.50, "net_dex": 322266.83 }
]
}
}
What This Unlocks
- Replay dealer delta positioning at any minute — measure actual hedging flow at the open/close of historical moves.
- Backtest delta-flow strategies with point-in-time data — no lookahead bias.
- Decompose hedging pressure into delta (DEX) vs gamma (GEX) vs vanna (VEX) vs charm (CHEX) — needed for clean sensitivity analysis.
Related Historical Endpoints
- Historical GEX — gamma exposure by strike
- Historical VEX — vanna exposure
- Historical CHEX — charm exposure
- Historical Exposure Summary — composite GEX/DEX/VEX/CHEX with hedging estimates
- Historical API overview →