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How to Regenerate Thumbnails or New Image Sizes in WordPress

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How to Regenerate Thumbnails or New Image Sizes in WordPress

Recently, a WPBeginner reader asked for our help regarding an issue with images on their website. It all started when the user switched to a new theme, and the theme displayed thumbnails next to the excerpt of the post. The problem was that all new images that were uploaded after activating the theme were looking good, but all the old thumbnails looked ugly and distorted. The user tried to adjust image sizes in Settings » Media, but it didn’t solve the problem. In this article, we will show you how to regenerate thumbnails or new image sizes in WordPress.

By default when you upload an image to WordPress, it creates different sizes and saves them in the uploads folder. Previously, we published a tutorial on how to create additional image sizes in WordPress. Many WordPress themes take advantage of this feature and define new image sizes, but the problem is that these new image sizes are only applied on the images you upload after activating the theme. To solve this problem you need to generate new sizes for all previously uploaded images. This process is often referred to as regenerating thumbnails.

Video Tutorial

If you don’t like the video or need more instructions, then continue reading.

To generate images in newly defined image sizes, install and activate the Regenerate Thumbnails plugin. After activating the plugin, go to Tools » Regen. Thumbnails.

Regenerate Post Thumbnails

Pressing the regenerate thumbnail button will start generating new image sizes defined by your theme or in Settings » Media page. You can also regenerate image sizes for individual or multiple images in Media » Library.

Regenerate single image sizes or bulk generate

Regenerating images sizes does not affect your original upload. It creates additional copies of images in the newly defined sizes. It also does not delete previously created image sizes. You can delete the sizes if you are sure that you haven’t used those sizes anywhere on your website.

We hope this article resolves image size issues. If you have any questions regarding regenerate thumbnails, then let us know by leaving a comment below.


Editorial Staff at WPBeginner is a team of WordPress lovers led by Syed Balkhi. Page maintained by Syed Balkhi.

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  • http://www.wpbeginner.com/ WPBeginner Staff

    Regenerate Thumbnails is one of those plugins that you can install if the need arise. There is no point of keeping it on your site since it does nothing on its own until you explicitly tell it to regenerate image sizes.

  • http://www.HomeTips4Women.com tinagleisner

    It feels like this plugin will regenerate all sizes if you want but noone is stating that it does more than thumbnails?

    • http://www.wpbeginner.com/ WPBeginner Staff

      Yes it will regenerate all image sizes. If an image does exist in all defined sizes, then it will not regenerate another copy of that image.

  • http://www.wpbeginner.com/ WPBeginner Staff

    Lisa the problem is not with WordPress but with the theme you have chosen. This theme is using a larger image size 640×427 while the flickr image you inserted in your posts were 300×200 px.

    One possible workaround to that problem is to import external images in WordPress and then run Regenerate Thumbnails plugin.

    Make sure that you first create a complete WordPress backup before trying this solution.

  • http://www.wpbeginner.com/ WPBeginner Staff

    You can actually do some basic editing like cropping, resizing, rotating, images in WordPress. However, this can only be done after an image is uploaded to the server.

    Just to be extra clear on the topic, WordPress does store your image file in its original size. You can also create additional sizes if you need or remove sizes you don’t need.

  • http://www.wpbeginner.com/ WPBeginner Staff

    you probably need to regenerate thumbnails.

  • Flávia Pimentel

    Hi, there. I used the plugin and now I have 2 images as thumbnail. How do I delete old sizes? I only have the original image, after using the plugin it did not create a new media file.

  • Osama

    Hi.. It will regenerate only thumnails (feature images, popular posts on sidebars etc) or it will regenerate all the images on the website?

    • http://www.wpbeginner.com/ WPBeginner Support

      It will regenerate all the images you uploaded using media uploader in WordPress. Not the images in your themes, plugins, or images you uploaded manually.

  • Mike

    I am using Solostream’s theme WP-Clear 3.2.1, which uses the latest version of the Regenerate Thumbnails plugin, however when I run the regenerate thumbnails plugin, I get about an 80% failure on regenerating.

    I have even gone so far as to temporarily set the upload directory and files permissions to 777, and it still fails.

    Any ideas? Should I just purchase another theme that will work.

    Thanks

    PS I can’t remember the exact error message as it was all in some code and about 200 characters long, but I have asked around in different forums. You guys are my last hope!

  • GABRIELA

    YOU ARE AWESOMEEE!!!!
    YOU SOLVE ALL MY PROBLEMSSS !!!
    THANKS A LOT REALLY!

  • Zad I.

    I had an issue with the thumbnail version of some of my images being broken in the media section. When I checked the folder it was referring, it was not there for some reason, but the original size version was still there. Using this plugin not only fixed my problem, but also saved me a lot of time from having to manually resize each image through photoshop.

    For anyone using this plugin, since I only had about 6-7 broken thumbnail images in the media section, I just selected regenerate image on each one selectively instead of doing it to all images just to be on the safe side. Everything worked well.

    Thanks.