Кнопка Bootstrap Circle
<button type="button" class="btn btn-info btn-circle">
<i class="glyphicon glyphicon-ok"></i>
</button>
Azizul7m
<button type="button" class="btn btn-info btn-circle">
<i class="glyphicon glyphicon-ok"></i>
</button>
<button type="button" class="btn btn-primary btn-circle btn-sm">Blue</button>