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guideBase64 image upload adapter

The Base64 image upload adapter converts inserted images into Base64-encoded strings in the editor output. The images are stored with other content in the database without any server-side processing.

Remember that while Base64 upload is an easy solution, it is also highly inefficient. The image file is kept as data in the database, generating a much heavier data load and higher transfer. Base64 images are never cached by the browser so loading and saving such data will always be slower.

This can be troublesome for some features: revision history may hence take longer to load revisions. The same applies to comments. Content with Base64 images may also exceed the allowed file size when your document is exported to PDF or to Word.

Therefore using the Base64 feature is a less efficient option to use than some other available ones. Check out the comprehensive image upload overview guide to learn about other ways to upload images into CKEditor 5.

# Demo

Use the editor below to see the adapter in action. Open the web browser console and click the button below the editor to see the base64–encoded image in the editor output data.

CKEditor 5 offers multiple ways to include images in your rich content. You can choose whichever best suits your needs. Use the classic interface or boost your productivity with advanced image handling.

Paste or drag and drop an image directly into the editor. You can also use the insert image button in the toolbar.

This demo presents a limited set of features. Visit the feature-rich editor example to see more in action.

# Installation

This feature is enabled by default in the superbuild only.

First, install the @ckeditor/ckeditor5-upload package:

npm install --save @ckeditor/ckeditor5-upload

Add the Base64UploadAdapter to your plugin list:

import { Base64UploadAdapter } from '@ckeditor/ckeditor5-upload';

    .create( document.querySelector( '#editor' ), {
        plugins: [ Base64UploadAdapter, /* ... */ ],
        toolbar: [ /* ... */ ]
    } )
    .then( /* ... */ )
    .catch( /* ... */ );

Once enabled in the plugin list, the Base64 image upload adapter works out–of–the–box without any additional configuration.

Read more about installing plugins.

# Configuration

# Configuring allowed file types

The allowed file types that can be uploaded should actually be configured in two places:

  • On the client side, in CKEditor 5, restricting image upload through the CKEditor 5 UI and commands.
  • On the server side, in your server configuration.

# Client-side configuration

Use the image.upload.types configuration option to define the allowed image MIME types that can be uploaded to CKEditor 5.

By default, users can upload jpeg, png, gif, bmp, webp, and tiff files. You can customize this behavior to accept, for example, SVG files (in this case use the svg+xml type).

# Server-side configuration

It is up to you to implement any filtering mechanisms on your server to restrict the types of images allowed to be uploaded.

# What’s next

Check out the comprehensive Image upload overview to learn more about different ways of uploading images in CKEditor 5.

See the Image feature guide to find out more about handling images in CKEditor 5 WYSIWYG editor.

# Contribute

The source code of the feature is available on GitHub at