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

# Offline Support

> Allow respondents to complete link surveys even without an internet connection.

Offline support lets respondents fill out link surveys when they lose connectivity. Responses are stored locally on the device and automatically synced to the server when the connection is restored.

## How it Works

1. When enabled, survey responses are saved to the browser's IndexedDB as the respondent progresses.
2. If the respondent goes offline, they can continue filling out the survey without interruption.
3. When the connection is restored, all pending responses are automatically synced to the server.
4. A status alert is shown at the top of the page to inform the respondent of the current state (offline, syncing, or synced).

<Note>
  Offline support is only available for **link surveys**. App and website surveys are not affected.
</Note>

## Enabling Offline Support

Append the `offlineSupport=true` query parameter to your survey link:

```sh theme={null}
https://formbricks.com/s/your-survey-id?offlineSupport=true
```

You can combine it with other query parameters:

```sh theme={null}
https://formbricks.com/s/your-survey-id?offlineSupport=true&source=Google&lang=de
```

## Limitations

* **File uploads** are not supported offline. Text, choice, number, and other non-file responses are fully queued.
* **Stale data** is automatically discarded after 24 hours if it was never synced.
* The alert banner is not shown when the survey is embedded via iframe (`isEmbed` mode).