How to delete WordPress theme

This tutorial will show you how to delete installed theme in WordPress WordPress is web software you can use to create a beautiful website or blog. We like to say that WordPress is both free and priceless at the same time. The core software is built by hundreds of community volunteers, and when you’re ready for more there are thousands of plugins and themes available to transform your site into almost anything you can imagine. Over 60 million people have chosen WordPress to power the place on the web they call “home” — we’d love you to join the family.

Remove theme from admin panel

1. Open WordPress admin panel

2. Go to Appearance>Themes

3. Activate the default WordPress theme (Twenty Ten). You can’t delete the active theme. Do not delete the default WordPress theme.

4. Now you can delete any other theme. Use the Delete link under the theme thumbnail

Removing theme through FTP

1. Using FTP manager login to your server and open the WordPress installation folder

2. Go to wp-content/themes and delete the required folder.

Feel free to check the detailed video tutorial below:
How to delete WordPress theme