Image Classes

Define reusable transformation presets

Image Classes let you create named presets for Dynamic Images API transformations, making it easier to maintain consistent image styles across your website.

Why use Image Classes?

Instead of this:

https://yourzone.b-cdn.net/image.jpg?width=300&height=200&quality=85&sharpen=true

Use this:

https://yourzone.b-cdn.net/image.jpg?class=thumbnail

Benefits:

• Consistent transformations across your site
• Easier to update styles (change the class, not every URL)
• Improved cache hit rates
• Enhanced security with forced transformation classes

Creating Image Classes

1. Navigate to Image Classes

   Navigate to Optimizer → Image Classes

   
2. Define your class properties

   Configure the transformation settings for your image class:

   • Width, height, aspect ratio
   • Quality settings
   • Filters and effects
   • Any Dynamic Images API parameter

   
3. Save the class

   Save the class with a memorable name that describes its purpose (e.g., thumbnail, hero, product-mobile).

Forced transformation classes

Enable this option to restrict the Dynamic Images API to only use predefined classes:

• Improves cache efficiency (fewer unique transformations)
• Prevents arbitrary transformations (security benefit)
• Returns 403 for invalid or missing classes

This is recommended for production environments where you want tight control over image transformations.

Example classes

Property	thumbnail	hero_image	mobile_product
Width	300px	1920px	800px
Height	200px	-	-
Aspect Ratio	-	16:9	-
Quality	80%	90%	75%
Additional Settings	Sharpen: true	-	Smart optimization: enabled