If you'd like to back up the content of your website, you can export your site to a zip file. While it isn't possible to import this file back into Weebly, it does allow you to save an offline backup of your site for safe keeping or to even move the site to another host.
Go to Settings > General, then scroll down to the Archive section. Enter your email in the field and click Email Archive.
All done! Keep in mind that blog pages will not be exported as they rely directly on our database. Some of our elements also may not work correctly when hosted elsewhere, like our Contact Form and Slideshow elements. If possible, you should try to keep your website hosted on Weebly in order to easily update it.