How to Change Font Size in WordPress: 5 Easy Ways

Knowing how to change font size in WordPress takes about two minutes. The right method depends on how much text you want to resize.

This guide was tested in October 2026 on WordPress 7.1.3. I used the Twenty Twenty-Five block theme for the editor steps and Twenty Twenty-One for the classic ones. I also read the Advanced Editor Tools listing and the WordPress notes on fluid font sizes.

You will learn five ways to change font size: a single block, the whole site, size presets, CSS and a plugin. Then you will see which unit to pick and how to fix a change that does not show.

How to Change Font Size in WordPress for a Single Block

To change the font size of one block, select the block, open the Block tab and choose a size under Typography. You can pick a preset such as S, M or L, or enter your own value. The change applies to that block only.

Size and family are separate settings. Read how to change fonts in WordPress before you touch the size.

Follow these steps in the block editor:

1. Open the editor: Edit the post or page that holds the text.
2. Select the block: Click the paragraph or heading you want to resize.
3. Open Typography: In the Block tab of the sidebar, scroll to the Typography panel.
4. Pick a preset: Click S, M, L, XL or XXL under Font size.
   
5. Or enter your own size: Click the sliders icon. Type a number and choose a unit.
   
6. Save the change: Click Update to apply it to the live page.

A preset is saved as a class such as has-large-font-size. A custom value is saved as an inline style, and my test of 1.5 rem produced style="font-size:1.5rem". On my test site the custom field opened with rem as its default unit.

Tip: If the Font size control is missing, click the three dots next to Typography and tick Size. The same menu has Reset all, which sends the block back to the theme size.

How to Change Font Size in WordPress for the Whole Site

Here is how to change font size in WordPress for the whole site. Open the Site Editor and choose Styles. Set a size for Text or Headings. The new size then applies to every page that uses that element. You never edit single posts.

For block themes, the Site Editor is the cleanest way to make a WordPress change font size across every page. Follow these steps:

1. Open the Site Editor: Go to Appearance > Editor.
2. Open Styles: Click Styles in the left menu.
3. Choose Typography: The screen lists Typesets, Fonts, Elements and Font sizes.
   
4. Open an element: Click Text for body copy, or Headings for titles.
5. Pick a size: Click S, M, L, XL or XXL under Font size.
   
6. Save: Click the Review changes button and then Save.
   

In my test, the Text element started on L. I moved it to XL and saved. Body text on the front end then grew from about 21.8 px to 31.8 px at 1,280 px wide.

How to Change Heading Sizes

Click Headings and choose a level from the row that reads All, H1, H2 and so on up to H6. On my site the Font size control showed under H1 but not under All. Set each level on its own.

Keep a clear step between levels. H2 should stay smaller than H1. A heading that is the same size as its parent looks like a mistake.

How to Increase Font Size in WordPress With Size Presets

To increase font size in WordPress for many blocks at once, edit the size presets in Styles. Each preset, such as Medium or Large, is one value that every block using it shares. Change it once and all of those blocks follow.

Use these steps to edit a preset:

1. Open the presets: In Styles, click Typography and then Font size presets.
   
2. Choose a preset: Click Medium, Large or any other size in the list.
3. Set the size: Type a new value, or use the Fluid typography switch and set a minimum and maximum.
   
4. Save: Click the Review changes button and then Save.

The five presets on my Twenty Twenty-Five test site came from the page’s own CSS. Other themes use other values. Check yours in this screen. At the browser default of 16 px, Medium runs from 16 to 18 px.

Preset	Smallest	Largest
Small	0.875 rem	0.875 rem (fixed)
Medium	1 rem	1.125 rem
Large	1.125 rem	1.375 rem
Extra Large	1.75 rem	2 rem
Extra Extra Large	2.15 rem	3 rem

How to Change Font Size in WordPress With CSS

To change font size with CSS, open Appearance > Customize > Additional CSS and add a font-size rule for the element. Click Publish and the new size shows on the live site. This works in any theme that has the Customizer.

Follow these steps in a classic theme:

1. Open the Customizer: Go to Appearance > Customize.
2. Open Additional CSS: Click Additional CSS at the bottom of the list.
   
3. Add your rule: Type the CSS for the element you want to change, and watch the preview.
   
4. Publish: Click Publish.

Here is the rule from my test:

.entry-content p {
	font-size: 1.5rem;
}

On Twenty Twenty-One that rule moved paragraph text from 20 px to 24 px. The selector .entry-content p is specific to that theme. Right-click your own text and choose Inspect to find the class your theme uses.

The Customizer in Twenty Twenty-One has no font size control at all, and it has no link color setting either. Its list holds Site Identity, Colors and Dark Mode, Background Image, Menus, Widgets, Homepage Settings, Excerpt Settings and Additional CSS. So on a theme like this, CSS is the route.

Block themes hide the Customizer. In the Site Editor, open Styles, click the three dots and choose Additional CSS instead.

A fluid rule for headings looks like this. It grows with the screen between 1.5 rem and 2.25 rem:

h2 {
	font-size: clamp(1.5rem, 1.2rem + 1.5vw, 2.25rem);
}

Note: WordPress saves Additional CSS for each theme. Switching themes leaves it behind. The core ticket Additional CSS lost when changing themes is still open. Copy your CSS before you switch.

To edit your theme’s own files safely, follow our guide to create a WordPress child theme. A child theme keeps your changes when the parent theme updates. Our guide on how to change font color in WordPress covers the matching color rules.

How to Change Font Size in WordPress With a Plugin

A plugin helps when you still write in the Classic block. Advanced Editor Tools adds a Font Sizes dropdown to the Classic block toolbar that lets you resize selected text. It adds no font size control to the block editor, which already has its own.

On the WordPress.org listing in October 2026, Advanced Editor Tools showed 1+ million active installations. It had a 4.5 rating from 354 ratings and was tested up to WordPress 7.1.3.

Use these steps to add the dropdown:

1. Install the plugin: Go to Plugins > Add Plugin and search for Advanced Editor Tools. Click Install and then Activate.
2. Open its settings: Go to Settings > Advanced Editor Tools and open the Classic Editor tab.
3. Add the button: Drag Font Sizes from the unused buttons into the toolbar.
   
4. Save the settings: Click Save Changes.
5. Resize text: Add a Classic block, click Edit, select the text and open Font Sizes.
   

The dropdown on my test site offered 8pt, 10pt, 12pt, 14pt, 18pt, 24pt and 36pt. Choosing 24pt wrapped my text as <span style="font-size: 24pt;">.

That is an inline style on every resized span. To change the size later, you must edit each one. For a whole site, a preset or a CSS rule is easier to maintain.

How to Pick px, rem or Fluid Font Sizes

Use rem for body text, px for fine details and a fluid clamp() size for headings. A rem value follows the base size a visitor sets in the browser. A fluid size moves with the screen width between a minimum and a maximum.

Size matters less if the font itself is hard to read. Compare the best fonts for WordPress first.

Accessibility is the main reason to prefer rem. The W3C success criterion WCAG 1.4.4 Resize Text asks that text can be enlarged up to 200 percent without losing content or function. It is a Level AA requirement.

WordPress added fluid font sizes in version 6.1. The WordPress core team’s note on fluid font sizes says a theme turns them on with settings.typography.fluid in theme.json. It also says they work only for sizes written in px, em or rem.

You saw this in the presets table. Medium in my test theme is clamp(1rem, 1rem + ((1vw - 0.2rem) * 0.196), 1.125rem). It never drops below 16 px or grows past 18 px.

Which Method Should You Use?

Use block settings for one-off text and the Site Editor for site-wide changes in a block theme. Use CSS when your theme is classic, and use a plugin only for the Classic block. Presets sit between the two, because one edit reaches every block that uses the size.

A mix works well. Set the base WordPress font size once in Styles or CSS, and change single blocks only for real exceptions. A page with a size on every block is hard to keep consistent.

If you manage several client sites, a WordPress care plan can cover theme updates and style checks. That keeps a typography change from breaking after the next update.

Why Your Font Size Change Is Not Showing

Most failed font size changes come from a cache or from a more specific rule that wins over yours. Clear your caches first and then check what overrides the size you set. Work through this list in order. Each check takes under a minute:

• Cache: Purge your caching plugin and your browser cache. Then reload the page.
• A block-level size: A size set on one block beats the global size. Select the block and reset its Typography.
• A more specific CSS rule: Right-click the text, choose Inspect and look for a rule that wins over yours.
• Plugin widgets: A chatbot or form plugin loads its own styles. Check that plugin’s settings.
• Theme files: An edit made in the parent theme’s style.css is lost on update. Core files such as index.php carry the same risk. Use a child theme or Additional CSS.

Also check the page at phone width. A fluid or media-query size can look right on desktop and wrong on mobile.

Conclusion

Now you know how to change font size in WordPress for one block, the whole site and classic setups. Use block settings for exceptions, Styles for the base size and CSS when your theme has no size control.

Prefer rem or fluid sizes over px so text still follows the visitor’s browser setting. Test the page on a phone before you finish. If a change does not show, clear the cache and look for a more specific rule.

Frequently Asked Questions (FAQs)