How to Adjust Mobile Font Size and Padding in Letterhead

Blocks in the composer have mobile-specific style settings, so you can tune readability and spacing for phones and tablets without changing the desktop layout.

Adjust mobile font size

1. Open your newsletter and click the block you want to adjust.
2. In the settings panel, scroll to the Styles section and expand Text.
3. Change the Mobile Font Size value.

Changes apply only on mobile devices. Use this when text looks too small on phones or headings feel oversized on small screens.

Adjust mobile padding

1. In the same Styles section, expand Block.
2. Turn on the Mobile Padding switch.
3. Set the padding values for top, bottom, left, and right.

The values apply only on phones and other small screens. Extra padding keeps text from feeling cramped, and tighter padding gives your content more room on a narrow screen.

Leave the switch off and the block keeps its regular padding at every screen size — turn it on only for blocks that should be spaced differently on phones.

New blocks start from the mobile padding in your newsletter-wide design settings, so you usually only need a block’s own switch when one block should differ from the rest.

Preview before sending

Switch to the Mobile Preview in the editor to check spacing, alignment, and readability, and adjust until it looks right.

For newsletter-wide mobile width and other design defaults, see How do I use the new design settings?

To hide a block on phones or computers entirely rather than restyling it, see Show a Block on Desktop or Mobile Only.