Title: Remove Post Thumbnail classes
Last modified: August 20, 2016

---

# Remove Post Thumbnail classes

 *  Resolved [christopherburton](https://wordpress.org/support/users/christopherburton/)
 * (@christopherburton)
 * [13 years, 10 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/)
 * How could I remove the post thumbnail classes within functions.php?
 * I saw this [post](http://wordpress.org/support/topic/remove-class-from-the_post_thumbnail?replies=4#post-1987679)
   however, it gave an error.

Viewing 12 replies - 1 through 12 (of 12 total)

 *  [wpismypuppet](https://wordpress.org/support/users/wordpressismypuppet/)
 * (@wordpressismypuppet)
 * [13 years, 10 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907046)
 * What’s the error?
 *  Thread Starter [christopherburton](https://wordpress.org/support/users/christopherburton/)
 * (@christopherburton)
 * [13 years, 10 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907050)
 * Warning: preg_replace() [[function.preg-replace](https://wordpress.org/support/topic/remove-post-thumbnail-classes/function.preg-replace?output_format=md)]:
   Unknown modifier ‘c’ in C:\Users\Chris\Desktop\wamp\www\wordpress\wp-content\
   themes\murtaugh-HTML5-Reset-Wordpress-Theme-8aa6329\functions.php on line 164
 * Line 164: `$output = preg_replace('<code>class=&quot;(.*?)&quot;</code>', '',
   $output);`
 *  [wpismypuppet](https://wordpress.org/support/users/wordpressismypuppet/)
 * (@wordpressismypuppet)
 * [13 years, 10 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907052)
 * It’s the correct code, but an incorrect preg_replace. Use this… I tested and 
   it works:
 *     ```
       //remove class from the_post_thumbnail
       function the_post_thumbnail_remove_class($output) {
       	$output = preg_replace('/class=".*?"/', '', $output);
       	return $output;
       }
       add_filter('post_thumbnail_html', 'the_post_thumbnail_remove_class');
       ```
   
 *  Thread Starter [christopherburton](https://wordpress.org/support/users/christopherburton/)
 * (@christopherburton)
 * [13 years, 10 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907056)
 * Really appreciate that.
 *  [wpismypuppet](https://wordpress.org/support/users/wordpressismypuppet/)
 * (@wordpressismypuppet)
 * [13 years, 10 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907059)
 * You are welcome…
 *  Thread Starter [christopherburton](https://wordpress.org/support/users/christopherburton/)
 * (@christopherburton)
 * [13 years, 10 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907063)
 * For some reason it leaves off the trailing ‘/>’ of the img tag.
 * **Edit:** My fault.
 *  [wpismypuppet](https://wordpress.org/support/users/wordpressismypuppet/)
 * (@wordpressismypuppet)
 * [13 years, 10 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907065)
 * Mine is still there… make sure you check your source code, and not just through
   Firebug or something… my Firebug leaves it off, but my source code shows it.
 *  Thread Starter [christopherburton](https://wordpress.org/support/users/christopherburton/)
 * (@christopherburton)
 * [13 years, 10 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907068)
 * Yeah, it’s all good. I didn’t see it at first but it’s there.
 *  [aares](https://wordpress.org/support/users/aares/)
 * (@aares)
 * [13 years, 2 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907413)
 * Hello, I have the same issue except that I seem to know less about codes than
   both of you. I’m working with Gridportfolio theme. Could you tell me where to
   put the code posted above and other details i should know for the ‘post-thumbnails’
   to be disabled?
    Thanks!
 *  Thread Starter [christopherburton](https://wordpress.org/support/users/christopherburton/)
 * (@christopherburton)
 * [13 years, 2 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907414)
 * The code above goes into the functions.php file.
 *  [rabeloalexandre](https://wordpress.org/support/users/rabeloalexandre/)
 * (@rabeloalexandre)
 * [12 years, 12 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907423)
 * Olá, tudo bem?
    Desculpa o encomodo, mas é que estou a procura de alguém pra 
   me quebrar um galho. Seguinte, tenho esse blog [http://www.valmirlima.com.br](http://www.valmirlima.com.br)
   que estou programando, porém ele é meio diferente dos outros, porque mesmo se
   eu não inserir imagem no post, aparece esse thumbnail na página principal. Como
   a maioria dos posts no blog não tem imagem, fica estranho né. Daí quero saber
   se voces podem me dar essa força, porque já procurei nos códigos e nada. Eu quero
   que apareça imagem na home apenas quando eu colocar imagem destacada, quando 
   eu não colocar, é pra aparecer só o título e uma prévia do texto mesmo, como 
   é na maioria dos blogs. Serei muito grato!
 *  [Michael](https://wordpress.org/support/users/alchymyth/)
 * (@alchymyth)
 * [12 years, 12 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907424)
 * [@rabeloalexandre](https://wordpress.org/support/users/rabeloalexandre/)
 * please post in English.
 * and [start a new topic](http://wordpress.org/support/forum/how-to-and-troubleshooting#postform).

Viewing 12 replies - 1 through 12 (of 12 total)

The topic ‘Remove Post Thumbnail classes’ is closed to new replies.

## Tags

 * [featured image](https://wordpress.org/support/topic-tag/featured-image/)
 * [functions](https://wordpress.org/support/topic-tag/functions/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 12 replies
 * 5 participants
 * Last reply from: [Michael](https://wordpress.org/support/users/alchymyth/)
 * Last activity: [12 years, 12 months ago](https://wordpress.org/support/topic/remove-post-thumbnail-classes/#post-2907424)
 * Status: resolved

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