Rate limits - Cal — ContextQMD

<Warning> **API v1 is deprecated and will be discontinued on February 15, 2026.** Please migrate to [API v2](/api-reference/v2/introduction) as soon as possible. </Warning>

We limit the number of calls you can make over a certain period of time. Rate limits vary and are specified by the following header in all responses:

<table> <thead> <tr> <th>Header</th> <th>Description</th> </tr> </thead> <tbody> <tr> <td>X-RateLimit-Limit</td> <td>The maximum number of requests that the consumer is permitted to make.</td> </tr> <tr> <td>X-RateLimit-Remaining</td> <td>The number of requests remaining in the current rate limit window.</td> </tr> <tr> <td>X-RateLimit-Reset</td> <td>The time at which the current rate limit window resets in UTC epoch seconds.</td> </tr> </tbody> </table>

When the rate limit is exceeded, an error is returned with the status "429 Too Many Requests":

json

{
  "error": {
    "code": "too_many_requests",
    "message": "Rate limit exceeded",
  }
}