Options Cumulative Net Flow API

Endpoint

GET /v1/flow/options/{symbol}/cumulative

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

Parameters

Name	In	Required	Default	Description
`symbol`	path	yes	-	Underlying symbol
`minutes`	query	no	240	Window size, clamped to `1..10080`
`expiry`	query	no	-	Filter to a single expiration cycle, `YYYY-MM-DD`. Omit to include all expiries.

curl -H "X-Api-Key: YOUR_API_KEY" \
  "https://lab.flashalpha.com/v1/flow/options/SPY/cumulative?minutes=240"

import requests

resp = requests.get(
    "https://lab.flashalpha.com/v1/flow/options/SPY/cumulative",
    headers={"X-Api-Key": "YOUR_API_KEY"}
)
data = resp.json()
print(f"Cumulative net: {data['points'][-1]['cumulative']:,}")

const resp = await fetch(
  "https://lab.flashalpha.com/v1/flow/options/SPY/cumulative",
  { headers: { "X-Api-Key": "YOUR_API_KEY" } }
);
const data = await resp.json();
console.log("Cumulative net: " + data.points[data.points.length-1].cumulative.toLocaleString());

API Key

Response

{
  "symbol": "SPY",
  "minutes": 240,
  "count": 3,
  "points": [
    {
      "ts": "2026-05-12T15:00:00Z",
      "netVolume": 1820,
      "cumulative": 1820,
      "vwap": 1.32,
      "tradeCount": 3045
    },
    {
      "ts": "2026-05-12T15:01:00Z",
      "netVolume": -480,
      "cumulative": 1340,
      "vwap": 1.31,
      "tradeCount": 2980
    },
    {
      "ts": "2026-05-12T15:02:00Z",
      "netVolume": 2150,
      "cumulative": 3490,
      "vwap": 1.34,
      "tradeCount": 3210
    }
  ]
}

Key Response Fields

Field	Type	Description
`symbol`	string	Uppercase underlying symbol
`minutes`	integer	Requested/effective minute window
`count`	integer	Number of points returned
`points[]`	array	Cumulative flow points: `ts`, `netVolume`, `cumulative`, `vwap`, `tradeCount`

Errors

Status	Description
`403`	Requires Alpha plan or higher
`502`	Upstream flow data source unavailable

About

Per-minute net option volume joined with a running cumulative across the window. This is the easiest way to plot a single-line directional-flow chart and spot the inflection points where buying pressure flipped to selling.

Common Use Cases

Plot a single-line cumulative-flow chart - draw cumulative over ts to show net directional pressure building or unwinding across the session
Find the inflection point - watch where per-minute netVolume flips sign and cumulative rolls over to mark the moment buyers handed off to sellers
Build a divergence signal - compare the cumulative slope against the underlying's price trend to flag flow leading or fading the move
Attribute flow by session - difference cumulative across timestamps to weigh morning versus afternoon net flow
Screen for stretched tapes - flag symbols whose cumulative has drifted far from zero as mean-reversion or continuation candidates
Confirm with VWAP and activity - read vwap and tradeCount alongside each point to check the cumulative move is backed by real volume

Complementary endpoints

Options History - the per-minute buckets this running total is built from
Options Summary - the day's aggregate totals at the end of the curve
Options Recent - the individual prints feeding the net-volume series
Flow Summary - higher-level flow analytics tie-in