Answers for "bootstrap 4 btn small size"

large button in bootstrap

<!-- Large buttons -->
<button type="button" class="btn btn-primary btn-lg">Large button</button>

<!-- Medium Buttons -->
<button type="button" class="btn btn-primary">Large button</button>

<!-- Small Buttons -->
<button type="button" class="btn btn-primary btn-sm">Large button</button>

<!-- Block Buttons -->
<button type="button" class="btn btn-primary btn-lg btn-block">Block level button</button>

bootstrap 4 button size

<button type="button" class="btn btn-primary btn-lg">Large button</button>
<button type="button" class="btn btn-secondary btn-sm">Small button</button>