How to change default image sizes

Go to appearance/editor and select Sporty-WP.

Open the includes/functions.php file:

You will find two add_image_size functions:

Find:

add_image_size( 'sporty-blog-image', 964, 428, true);
add_image_size( 'sporty-large-blog-image', 1024, 285, true);

Change the values as you want. First value is width, second value is height. For example, let’s change only height values:

add_image_size( 'sporty-blog-image', 964, 600, true);
add_image_size( 'sporty-large-blog-image', 1024, 400, true);

Click Save.

Changing Image Sizes for Slider

Navigate to plugins/editor and select Sporty FlexSlider. Open the sporty-flexslider.php:

Find:

add_image_size( 'flexslider-image', 1024, 285, true);

Replace:

add_image_size( 'flexslider-image', 1024, 400, true);

Save!

Let images work!

Now, after changes done and everything saved, you can do two things to let the changed take effect.

Possibility #1:

Re-upload your images.

Possibility #2:

Install and activate Regenerate Thumbnails and navigate to Tools/regenerate thumbnails. The plugin can crop all your images in your media library.