---
title: "Kalshi Open Interest History"
method: GET
path: "/gateway/v1/prediction-market/kalshi/open-interest"
tags: ["Prediction Market"]
---

# Kalshi Open Interest History

`GET /gateway/v1/prediction-market/kalshi/open-interest`

## Request

- Base URL: `https://api.asksurf.ai`
- URL: `https://api.asksurf.ai/gateway/v1/prediction-market/kalshi/open-interest`
- Auth: HTTP bearer

Daily open interest time series for a Kalshi market.

**Data refresh:** ~30 minutes

## Query parameters

- `ticker` string, required: Market ticker identifier. Use GET /v1/prediction-market/kalshi/markets or GET /v1/search/prediction-market?platform=kalshi&q={keyword} to discover valid tickers.
- `time_range` '7d' | '30d' | '90d' | '180d' | '1y': Window of history to return: `7d`, `30d`, `90d`, `180d`, or `1y`. This endpoint uses `time_range` only — it does NOT accept `interval`.

## Response `200`

OK

- DataResponseKalshiOIPoint
  - `$schema` string, uri: A URL to the JSON Schema for this object.
  - `data` KalshiOIPoint[], nullable, required
    - `open_interest` number, double, required: Open interest on this date (contracts)
    - `timestamp` integer, required: Unix timestamp in seconds (midnight UTC for the trading day)
  - `meta` OffsetMeta, required
    - `cached` boolean, required: Whether this response was served from cache
    - `credits_used` integer, required: Credits deducted for this request
    - `empty_reason` string: Hint explaining why the data array is empty, when applicable
    - `has_more` boolean: Whether more items may exist beyond this response. For offset-paged endpoints, continue with a larger offset. For time-series endpoints without offset/cursor controls, true means the requested time range hit an upstream cap; narrow from/to to continue. Omitted when exhaustion cannot be proven.
    - `limit` integer, required: Maximum number of items returned in this response
    - `offset` integer, required: Number of items skipped (pagination offset)
    - `total` integer: Total number of matching items (before pagination). Omitted when total is unknown.
    - `watermark` integer: Warehouse watermark (Unix seconds) this response was computed at, on warehouse-backed endpoints (e.g. Hyperliquid /trades/aggregate) — rows up to this time come from the warehouse, newer rows from the live tail. Omitted elsewhere.

## Other responses

- `default`: Error

---

[API](https://skmtc.dev/asksurf/apis/asksurf-public-rest-api.md) - [All operations](https://skmtc.dev/asksurf/apis/asksurf-public-rest-api/llms.txt) - [OpenAPI document](https://skmtc.dev/asksurf/apis/asksurf-public-rest-api/revisions/91774fdd5302?raw)