> For the complete documentation index, see [llms.txt](https://docs.sheet.link/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sheet.link/security.md).

# Security

## **Google Sheets Access**

Google has made it [easy to control who has access](https://support.google.com/docs/answer/2494822) to your current sheet. Keep in mind, SheetLink only works in sheets with the add-on installed and activated.

## API Keys & Authentication

From your google sheet, select **"Add-ons" > "SheetLink" > "🔐 Authentication"** for all apps requiring authentication.

All API and authentication keys are securely saved as [Google Document Properties](https://developers.google.com/apps-script/guides/properties) of the current Google Sheet only and **are never accessible by the SheetLink team**. App API keys can be used with respective SheetLink app formulas by anyone with access to the Google Sheet.

{% hint style="success" %}
The **"key=reset"** [option](/formulas/options.md) will reset the authentication for any app
{% endhint %}