Open Interest History

Open-interest time series (with mark price and funding at each sample) — history the exchange does not offer.

GET /v3/perps/oi/{instrument}

Open interest history

cURL

curl --request GET \
  --url https://api.polynode.dev/v3/perps/oi/{instrument} \
  --header 'x-api-key: <api-key>'

200

{
  "data": [
    {
      "funding_rate": "0.0000125",
      "mark_price": "64125",
      "open_interest": "65.19026",
      "timestamp": 1783739407813
    },
    {
      "funding_rate": "0.0000125",
      "mark_price": "64122",
      "open_interest": "65.19026",
      "timestamp": 1783739347801
    }
  ],
  "instrument_id": 6,
  "more": true,
  "symbol": "BTC-USD"
}

Open interest is normally only visible as a live number on the ticker. This endpoint gives you its history:

Each sample carries the mark price and funding rate at that moment, so OI-vs-price studies need no joins. Samples are minute-resolution, newest first.

Parameter	Description
after / before	Time window (Unix seconds or ms)
limit	Max samples (default 500, up to 5000)

The series accrues from July 9, 2026 onward. /v3/perps/open-interest/{instrument} is an alias of /v3/perps/oi/{instrument} — both forms work.

Authorizations

x-api-key · string · header · required

Path Parameters

instrument · string · required

Instrument id (e.g. 6), symbol (BTC-USD), or bare asset (btc).

Query Parameters

after · string

Only rows after this time (Unix seconds or ms).

before · string

Only rows before this time (Unix seconds or ms).

limit · integer

Max rows to return.

Response

200 - application/json

Success