Chrome Extension Documentation

The Alt Text Lab Chrome Extension makes it easy to generate descriptive alt text for any image on any website.

Right-click any public image, generate an alt text with a single click, and instantly copy it for use — even in admin panels.

Installation

Install the extension and connect it to your Alt Text Lab account using your API key.

Go to the Chrome Web Store
Click Install, then confirm the installation.
Open the extension popup from the toolbar (puzzle icon → Alt Text Lab → "Options")
Paste your API Key into the corresponding field.
Get your API Key here
How to generate an API Key
Once saved, the extension is ready to use.

Quickly generate alt text for any publicly accessible image using the right-click context menu.

Right-click on any image on a public web page.
Select “AltTextLab: Get alt text” from the context menu.
Wait a few seconds. A popup will appear in the top-right corner of the page showing the generated alt text.
You can now copy and use the alt text wherever needed.

Note: The image must be publicly accessible

Customize the extension behavior to fit your workflow and language preferences.

Open the extension settings via the toolbar → Alt Text Lab → Options. You can configure the following options:

Language – Select the language in which the alt text should be generated.
AI writing style – Control how detailed or minimal the alt text should be.
Choose between styles like descriptive, neutral, matter-of-fact, and minimal.
Learn more about writing styles →
Use keywords from web page – If enabled, the AI will consider keywords from the page to generate more relevant descriptions.
Auto-copy to clipboard – If enabled, the alt text will be automatically copied to your clipboard after generation.

Note: Auto-copy works only if the tab where the image is located remains active during generation.

If you're having trouble using the Chrome extension, check out these common issues and how to fix them: