Facebook 'Share' Button

I have this code from Facebook:

<div class="fb-like" data-href="https://domain.com/blog/" data-width="300" data-layout="button" data-action="like" data-show-faces="true" data-share="true"></div>

I need this button so people can share or like individual blog posts. I don't know what url to put in the data-href field...??

Thanks