.img-rounded {
-webkit-border-radius: 50%;
-moz-border-radius: 50%;
border-radius: 50%;
}
If you are using Blogger, go to "Edit HTML" and add it just before ]]></b:skin> tag.
Now when you want to make an image circular, just add "img-rounded" CSS class into it. Look at the example below:
<img class="img-rounded" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjux3immfOyXQGbu7hxseiwP8P7Wof9gypW0mnqLUyOAiXi3weQ7KhlGjIhtVYGmkzyNRIrJRkM5jVJT0NYj93HAX-Hu5aKnON6Zhc5cVmPDwfW358eS7pZZ1TUbnpSKemSkbwpuhyOKr8J/s320/df50754a21636a29dbd50bff8190e9fe%255B1%255D.jpg" />
Result:
