How to Change wordpress image thumbnail size and regenerate thumbnails
January 29, 2010 by: adminIt is very easy to change the wordpress default thumbnail size at any time. Login to your wordpress and go to
Settings->media
Wordpress thumbnail settings page
Here you can change the width and height as you required. If you tick the option "Crop thumbnail to exact dimensions (normally thumbnails are proportional)" then the thumbnail size will be exact same as you specified. It will be a cropped image. If you remove this tick, Wordpress will take either width or height to generate the thumbnail.
Now, if there are many articles already posted with lot of images and you want to regenerate all the thumbnails. Is there any easy solution?
Yes. There is a smart plugin called "Regenerate Thumbnails". Regenerate Thumbnails allows you to regenerate the thumbnails for all of your image attachments. This is very handy if you've changed any of your thumbnail dimensions (via Settings -> Media) after previously uploading images.
After installing this plugin got to its setting page and click regenerate thumbnails. It will regenerate thumbnails of all the images uploaded previously.
Thank you! Great help.
Should this also work for the post thumbnails?
I have tried this but the thumbnails are still forced to 100 x 100 px
I have also uploaded new pictures and select the thumbnailsize 300 x 300 but the post thumbnail is still too small.