# API status codes

## Status codes

The API server responds contain a status code specifying the status of the response. The table below lists all the status codes and messages returned by the API server:

| Code | Message                                         | Explanation                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| ---- | ----------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| 20   | OK                                              | The request was processed successfully. The response might also contain the **data** parameter containing data returned from the server.                                                                                                                                                                                                                                                                                                                                          |
| 22   | Maintenance mode                                | The API servers have entered in maintenance mode and cannot complete any requests. In this case you should try again later.                                                                                                                                                                                                                                                                                                                                                       |
| 30   | Missing mandatory parameter                     | The request does not contain one or more required parameters. There are at least 3 required parameters for every request: **apiKey**, **signature** and **action**. Other methods may also have extra mandatory parameters. Please check the API Reference for more information.                                                                                                                                                                                                  |
| 31   | Requests per second limit exceeded              | There were too many requests per second made with the same API key.                                                                                                                                                                                                                                                                                                                                                                                                               |
| 32   | Requests per minute limit exceeded              | There were too many requests per minute made with the same API key.                                                                                                                                                                                                                                                                                                                                                                                                               |
| 33   | Uploads per month exceeded                      | You have exceeded the maximum number of uploads allowed per month.                                                                                                                                                                                                                                                                                                                                                                                                                |
| 34   | File size too large                             | The file you have uploaded has a size that exceeds the maximum file size allowed. For more information please see the [limitations](https://developers.flipsnack.com/api-limitations) imposed by the API.                                                                                                                                                                                                                                                                         |
| 35   | Flipbook maximum pages number exceeded          | You have uploaded a document that exceeds the maximum of 500 pages allowed. For more information please see the [limitations](https://developers.flipsnack.com/api-limitations) imposed by the API.                                                                                                                                                                                                                                                                               |
| 36   | Multiple files upload not allowed               | Flipsnack API allows only one file per upload request. Upload requests are made via the [collection.create](https://developers.flipsnack.com/api-reference/api-method-collection.create) method.                                                                                                                                                                                                                                                                                  |
| 37   | Delete flipbook not available for this flipbook | *deprecated*                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| 38   | Flipbook is in processing state                 | Publishing a flipbook may take a few seconds. You can check the **collectionStatus** at regular intervals (e.g., every few seconds) using the [collection.getCollection](https://developers.flipsnack.com/api-reference/api-method-collection.getcollection) method. Continue making requests to [collection.getCollection](https://developers.flipsnack.com/api-reference/api-method-collection.getcollection) until the **collectionStatus** has a value other than processing. |
| 40   | Bad request                                     | <ul><li>You made a POST request for an API call that is not uploading files.</li><li>You made a GET request for an API call that uploads files.</li><li>Your request is incorrectly formatted or the URL is invalid.</li></ul>                                                                                                                                                                                                                                                    |
| 41   | Invalid credentials                             | The API key provided in the request is invalid.                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| 42   | Invalid action                                  | The API method you specified in the request is incorrect. Please see the API Reference for the list of possible methods.                                                                                                                                                                                                                                                                                                                                                          |
| 43   | Forbidden                                       | You are not allowed to access the specified flipbook: it has been deleted or the flipbook belongs to another user.                                                                                                                                                                                                                                                                                                                                                                |
| 44   | Invalid signature                               | The signature you provided is incorrect - it does not match the request.                                                                                                                                                                                                                                                                                                                                                                                                          |
| 45   | Invalid file format                             | The file you are trying to upload has an incorrect file type. For more information please see the [limitations](https://developers.flipsnack.com/api-limitations) imposed by the API.                                                                                                                                                                                                                                                                                             |
| 46   | Invalid flipbook hash                           | You are trying to access a flipbook that does not exist.                                                                                                                                                                                                                                                                                                                                                                                                                          |
| 47   | Invalid flipbook hash                           | You are trying to access a flipbook that does not exist.                                                                                                                                                                                                                                                                                                                                                                                                                          |
| 50   | Operation failed                                | An error occurred on the server and the request could not be completed. In this case you should resend the request after a few seconds. If the request still fails after several attempts, please contact us.                                                                                                                                                                                                                                                                     |