# How to tag and label sources in NotebookLM (Gemini Notebook) > Add tags to single NotebookLM (Gemini Notebook) sources, tag many at once and filter by tag with the Kortex extension. https://www.kortex-notebooklm.com/tutorials/how-to-tag-notebooklm-sources 1. [Tutorials](/tutorials) 2. How to tag and label sources in NotebookLM # How to tag and label sources in NotebookLM (Gemini Notebook) 2 minutes 6 steps Updated November 5, 2026 ## Quick answer Install the Kortex extension and open the Kortex Workspace. Choose Sources and tick the sources you want. Click Tags, then pick a tag or type a new name. Later, filter by that tag. ## Watch it first How to tag and label sources in NotebookLM (Gemini Notebook) Read the transcript Here's how to tag sources from Gemini Notebook, formerly NotebookLM, in the Kortex Workspace, and then filter by tag. Open the Workspace with the Dashboard button in the side panel, then choose Sources. It shows every source from all your notebooks. Tick each source you want to label. The search box and the filters help you find them. Click Tags in the toolbar, and pick a tag you've already made. Click Filter to show only sources with a tag. Tags also show in the Tags column. Notebooks have their own tags. In Notebooks, tick rows and choose Tags the same way. To rename, delete or create tags in one place, open Manage Space in the sidebar. It holds notebook, source and artifact tags. Tag your sources, then find them by tag. ## What you need - The [Kortex extension](https://chromewebstore.google.com/detail/kortex/hdapplggdhndkblofffknpmnnnnbncbn) in Chrome, Edge or Brave, and signed in - Notebooks with sources in Gemini Notebook (formerly NotebookLM) ## On this page 1. [Open the Sources view](#step-1) 2. [Select the sources](#step-2) 3. [Choose Tags](#step-3) 4. [Filter by the tag](#step-4) 5. [Tag whole notebooks too](#step-5) 6. [Rename or delete a tag everywhere](#step-6) 7. [If it doesn’t work](#trouble) 8. [Questions](#faq) 1. ## Open the Sources view Click the dashboard button in the side panel header to open the Kortex Workspace. Choose **Sources** in the sidebar. It lists every source from all your notebooks. [![The All Sources table in the Kortex Workspace with each source's type, notebook, tags and folder.](/media/features/all-sources.webp)](/media/features/all-sources.webp) Every source across your notebooks, with its tags and folder. 2. ## Select the sources Tick the checkbox on each source you want to label. To find them first, use the search box or the filters at the top of the table. 3. ## Choose Tags Click **Tags** in the toolbar. Pick a tag you have already made, or type a new name to create one. 4. ## Filter by the tag Click **Filter** to show only sources with a tag. The tags also show in the Tags column of the table. 5. ## Tag whole notebooks too Notebooks have their own tags. In the **Notebooks** view, tick rows and choose **Tags** the same way. 6. ## Rename or delete a tag everywhere Open **Manage Space** in the sidebar. There you can rename, delete and create notebook, source and artifact tags in one place. ## If it doesn’t work My tags are missing on another computer Check that you are signed in to Kortex with the same account on both computers. Then reload the Workspace. I cannot find Manage Space Manage Space is in the Workspace sidebar, under Views. Click the dashboard button in the side panel's header to open the Kortex Workspace. Then look for it there. The Sources view is empty Reload the Workspace and check that you are signed in. If you use more than one Google account, check the Notebooks from switch at the bottom of the sidebar. ## Questions people ask Something we missed? [Ask us](#contact). ### Are notebook tags and source tags the same set? No. Notebooks and sources have separate sets of tags. Manage Space shows both. You can rename or delete either one there. ### Can I tag many sources at once? Yes. Tick as many rows as you like. Then choose Tags once. ### Do tags show up in Gemini Notebook itself? Tags stay in Kortex and show in the Workspace. They are not Gemini Notebook's own labels. ## Keep going [Tags and source labels Colored tags for notebooks, and a separate set of tags for single sources.](/features/tags-and-source-labels) [Kortex docs The full reference for this feature, with every option.](/docs/all-sources) ### More tutorials - [How to see all your NotebookLM notebooks in one place](/tutorials/how-to-manage-all-notebooklm-notebooks-in-one-place) - [How to merge NotebookLM (Gemini Notebook) notebooks](/tutorials/how-to-merge-notebooklm-notebooks) - [How to organize NotebookLM notebooks into folders](/tutorials/how-to-organize-notebooklm-notebooks-into-folders) - [How to save a notebook template in NotebookLM](/tutorials/how-to-save-a-notebook-template-in-notebooklm) [All tutorials](/tutorials) ## Do it on your own notebooks. Install the Kortex extension and follow these steps on a notebook you already have. [Add to Chrome](https://chromewebstore.google.com/detail/kortex/hdapplggdhndkblofffknpmnnnnbncbn) 100,000+ users, rated 4.5 on the Chrome Web Store.