You're looking at the documentation for Tailwind CSS v2.

Object Fit

Utilities for controlling how a replaced element's content should be resized.

Default class reference

Class
Properties
object-containobject-fit: contain;
object-coverobject-fit: cover;
object-fillobject-fit: fill;
object-noneobject-fit: none;
object-scale-downobject-fit: scale-down;

Contain

Resize an element’s content to stay contained within its container using .object-contain.

<div class="bg-rose-300 ..."> <img class="object-contain h-48 w-full ..."> </div>

Cover

Resize an element’s content to cover its container using .object-cover.

<div class="bg-indigo-300 ..."> <img class="object-cover h-48 w-full ..."> </div>

Fill

Stretch an element’s content to fit its container using .object-fill.

<div class="bg-light-blue-300 ..."> <img class="object-fill h-48 w-full ..."> </div>

None

Display an element’s content at its original size ignoring the container size using .object-none.

<div class="bg-yellow-300"> <img class="object-none h-48 w-full ..."> </div>

Scale Down

Display an element’s content at its original size but scale it down to fit its container if necessary using .object-scale-down.

<div class="bg-green-300"> <img class="object-scale-down h-48 w-full ..."> </div>

Responsive

To control how a replaced element’s content should be resized only at a specific breakpoint, add a {screen}: prefix to any existing object fit utility. For example, adding the class md:object-scale-down to an element would apply the object-scale-down utility at medium screen sizes and above.

<div> <img class="object-contain md:object-scale-down ..." src="..."> </div>

For more information about Tailwind’s responsive design features, check out the Responsive Design documentation.

Customizing

Variants

By default, only responsive variants are generated for object-fit utilities.

You can control which variants are generated for the object-fit utilities by modifying the objectFit property in the variants section of your tailwind.config.js file.

For example, this config will also generate hover and focus variants:

 // tailwind.config.js  module.exports = {   variants: {   extend: {  // ... +  objectFit: ['hover', 'focus'],   }   }  }

Disabling

If you don't plan to use the object-fit utilities in your project, you can disable them entirely by setting the objectFit property to false in the corePlugins section of your config file:

 // tailwind.config.js  module.exports = {   corePlugins: {  // ... +  objectFit: false,   }  }