Hi, you can add the class text-center in the HTML:
<div class="col-lg-6 text-center">
<div class="custom-control custom-checkbox">
<input type="checkbox" class="custom-control-input" id="checkbox-1" checked="">
<label class="custom-control-label" for="checkbox-1">Regular checkbox</label>
</div>
<!-- Default checked -->
<div class="custom-control custom-checkbox checkbox-lg">
<input type="checkbox" class="custom-control-input" id="checkbox-2" checked="">
<label class="custom-control-label" for="checkbox-2">Large checkbox</label>
</div>
<!-- Default checked -->
<div class="custom-control custom-checkbox checkbox-xl">
<input type="checkbox" class="custom-control-input" id="checkbox-3" checked="">
<label class="custom-control-label" for="checkbox-3">Extra large checkbox</label>
</div>
</div>
CSS: (css/custom.css)
.checkbox-lg .custom-control-label::before,
.checkbox-lg .custom-control-label::after {
top: .8rem;
width: 1.55rem;
height: 1.55rem;
}
.checkbox-lg .custom-control-label {
padding-top: 13px;
padding-left: 6px;
}
.checkbox-xl .custom-control-label::before,
.checkbox-xl .custom-control-label::after {
top: 1.2rem;
width: 1.85rem;
height: 1.85rem;
}
.checkbox-xl .custom-control-label {
padding-top: 23px;
padding-left: 10px;
}