How do I set up responsive font sizes (RFS) and when should I disable it?

Asked on Jul 20, 2025

Answer

Responsive Font Sizes (RFS) in Bootstrap automatically adjusts font sizes based on the viewport size, enhancing readability across devices. You might want to disable it for specific elements where a fixed font size is necessary.

<!-- BEGIN COPY / PASTE -->
        <style>
            .no-rfs {
                font-size: 1.5rem !important;
            }
        </style>

        <p class="no-rfs">This text will not use RFS and will remain at 1.5rem.</p>
        <!-- END COPY / PASTE -->

Additional Comment:

Use the `.no-rfs` class to apply a fixed font size, overriding RFS.
RFS is beneficial for maintaining proportional text sizes across devices.
Disable RFS when precise control over font size is needed for design consistency.

✅ Answered with Bootstrap 5 best practices.