Add an image block to a page.

You can insert images into your page, then choose their size and whether to align them to the left, center, or right. You can also optionally include alt text and/or a caption on your image block.

Tip: For accessibility purposes, we highly recommend setting alt text for every image in your space.

Image block examples

Image blocks can display a single image or a gallery on your page, like this:

How to add images

There are two ways to add images to your content:

  1. Drag and drop the image from your file management system directly into an empty block on your page.

  2. Add an image block to your page and use the Select images side panel that appears on the right of the window.

If you follow the second process, you can choose to upload a file, select a previously-uploaded file, paste an image URL or add an image from Unsplash using the built-in search.

GitBook allows you to upload images up to 100MB per file.

Adding images for light & dark mode

You can set different images for the light and dark mode versions of your published site. GitBook will automatically display the correct image depending on the mode your visitor is in.

Note: GitBook doesn’t currently support light and dark mode images for certain cases, including page covers or image covers on cards.

Light and dark mode images through GitHub/GitLab Sync

You can also add light and dark mode images in Markdown through HTML syntax (<picture> and <source>).

For block images, use the <figure> HTML element with a <picture> and <source> in it:

Text before

      media="(prefers-color-scheme: dark)"
      alt="GitHub logo"
  <figcaption>Caption text</figcaption>

Text after

For inline images (images that sit inline with text), use the <picture> HTML element with a <source> in it:

Text before the image
    media="(prefers-color-scheme: dark)" />
    alt="The GitHub Logo"
and text after the image

Note: We don’t yet support GitHub-only syntax through #gh-dark-mode-only or #gh-light-mode-only.


  • Small – 25% of the image size

  • Medium – 50% of the image size

  • Large – 75% of the image size

  • Fit – Removes all size specifications and displays either at full size or capped at a maximum width of 735 pixels for larger images.

If your image is wider than the editor, GitBook will limit the image’s width to the editor’s width instead, and resizing will be based on this limit.

Note: When resizing images in an image gallery, the results can differ from resizing an individual image.

Resizing images through Git Sync

If you want more control over the sizing of your image, you can specify the exact size using Markdown in GitHub or GitLab.

When we export an image, we use the HTML tag <img/>. As per the specifications, we can specify the dimensions of the image using the width and height attributes, which only accept values in pixels or a combination of a number and a % sign. Valid variants for specifying the image dimensions are: <img width="100" /> Sets the image to 100 pixels wide <img width="100%" /> Sets the image to full size (although this will be limited by the editor)

Aligning images

By default, image blocks will show your image at its full size, aligned centrally.

Representation in Markdown

//Simple Block

//Block with Caption
![The GitBook Logo](

//Block with Alt text

<figure><img src="" alt="The GitBook Logo"></figure>

//Block with Caption and Alt text

<figure><img src="" alt="The GitBook Logo"><figcaption><p>GitBook Logo</p></figcaption></figure>

//Block with different image for dark and light mode, with caption
    <source srcset="" media="(prefers-color-scheme: dark)">
    <img src="" alt="GitHub logo">
  <figcaption>Caption text</figcaption>

If you are looking to embed external content into your pages, take a look at how to embed a URL.

Last updated