Does Wordpress have a way of changing the 'Natural' size of uploaded images?

Question

So here's my problem: I have a site with several articles on the homepage, these are using the featured image as a thumbnail (roughly 250x250). Then, for a single article (single.php) I'm using the same image (with the same call get_post_thumbnail). The issue is, I don't need to be loading 1600x800 images for thumbnails, but I do for display on a single article.

I've looked in to plugins like Multiple Featured Images so I could just have 2 different sizes of the same image, but this would require me to go back through every article and upload a scaled down image.

Basically, I want to upload one image, but use 2 different sizes of it for site speed reasons.

Any ideas?

Answer 1

Wordpress has built in sizes for your photos that it automatically creates when you upland an image.

You can call different ones by using

get_the_post_thumbnail( $post_id, 'thumbnail' );      // Thumbnail (Note: different to Post Thumbnail)
get_the_post_thumbnail( $post_id, 'medium' );         // Medium resolution
get_the_post_thumbnail( $post_id, 'large' );          // Large resolution
get_the_post_thumbnail( $post_id, 'full' );           // Original resolution

if those don't fit exactly what you're looking for you can create your own size too:

add_image_size( 'my-custom-size', 220, 180 ); // 220 pixels wide by 180 pixels tall, soft proportional crop mode

and then call it by the same as above:

get_the_post_thumbnail( $post_id, 'my-custom-size' );