> ## Documentation Index
> Fetch the complete documentation index at: https://docs.gammaflip.io/llms.txt
> Use this file to discover all available pages before exploring further.

# History: Timestamps

> Capture timestamps of one session date

## What it returns

The capture times (ISO 8601 UTC) available for one session date, oldest first.
Use it to pick an exact `at` for [`/history/snapshot`](/api-reference/history-snapshot).
The session date is the UTC date for crypto and the America/New\_York trading date
for TradFi (see [Historical data](/history#session-date)).

Costs **1 request** against your [daily quota](/rate-limits).

## Path parameters

<ParamField path="exchange" type="string" required>
  `bybit`, `deribit`, `okx`, `derive`, `combined` or `tradfi`. Venue subsets return
  `400 history_not_available`.
</ParamField>

<ParamField path="coin" type="string" required>
  Symbol, for example `BTC`, `QQQ`. Case-insensitive.
</ParamField>

## Query parameters

<ParamField query="date" type="string" required>
  Session date, `YYYY-MM-DD` (years 2020 to 2100).
</ParamField>

## Response

<ResponseField name="data" type="array">
  Capture timestamps of that session date, for example `"2026-10-05T13:30:00Z"`.
  Empty when there is no history for the date.
</ResponseField>

<ResponseField name="meta" type="object">
  `exchange`, `coin`, `symbol`, `exchange_resolved`, `market`, `units`,
  `docs_url`, `session_date` and your `rate_limit`.
</ResponseField>

## Errors

<ResponseField name="400 invalid_param" type="error">
  `date` is missing, not `YYYY-MM-DD`, or outside 2020 to 2100.
</ResponseField>

<ResponseField name="400 history_not_available" type="error">
  Venue subset. The body includes `valid_exchanges`.
</ResponseField>

<RequestExample>
  ```bash cURL theme={null}
  curl "https://api.gammaflip.io/api/v1/history/timestamps/tradfi/QQQ?date=2026-10-05" \
    -H "X-API-Key: gex_sk_your_key_here"
  ```
</RequestExample>

<ResponseExample>
  ```json 200 OK theme={null}
  {
    "data": [
      "2026-10-05T13:30:00Z",
      "2026-10-05T13:45:00Z",
      "2026-10-05T14:00:00Z",
      "2026-10-05T20:15:00Z"
    ],
    "meta": {
      "timestamp": "2026-10-06T10:00:00.000000+00:00",
      "exchange": "tradfi",
      "coin": "QQQ",
      "symbol": "QQQ",
      "exchange_resolved": "tradfi",
      "market": "tradfi",
      "units": "USD per 1% move of the underlying",
      "docs_url": "https://docs.gammaflip.io/data-dictionary",
      "session_date": "2026-10-05",
      "rate_limit": { "limit": 500, "remaining": 496, "reset": "2026-10-07T00:00:00+00:00" }
    }
  }
  ```
</ResponseExample>

<Note>
  The values above are illustrative and shortened.
</Note>


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