Font-size property
The CSS font-size property specifies the nominal size of an element’s rendered text.
Build a Website with ChatGPT
The CSS font-size property specifies the size of text rendered by an element.
- How it is used
- Uses font-size to control readable text and visual hierarchy in generated page CSS.
- How deep it goes
- Defines pixel-based sizing, gives common heading values, and introduces rem conversion without deeper CSS mechanics.
- Examples
- Shows `font-size: 20px;`, heading defaults, a tagline request for 24px, and an `.entry-text` class rule.
- What you can do after
- Apply it via CSS by setting and adjusting pixel or rem text sizes for page elements.
Read how Build a Website with ChatGPT explains font-size property →
Math for Web Design
The CSS font-size property specifies the nominal size of rendered text glyphs.
- How it is used
- Balances readable body copy and responsive headings by setting text size alongside line height, line length, and viewport constraints.
- How deep it goes
- Derives unit conversion, inheritance, readability formulas, and clamp() interpolation, while leaving some algebraic derivations as exercises.
- Examples
- Works through nested em headings, a 24px article, a repaired 20px post, and a fluid 4rem-to-8rem hero heading.
- What you can do after
- Apply it via CSS units and math functions to size readable text and create bounded fluid typography without JavaScript.
D3.js in Action, Third Edition
The CSS font-size property specifies the size of rendered text.
- How it is used
- Keeps SVG chart labels readable across desktop and phone screen sizes.
- How deep it goes
- Explains fixed sizes, proportional scaling, clamping, D3 application, and resize updates, without covering CSS internals.
- Examples
- Uses line-chart text, axis labels, technology labels, count labels, linear scales, and resize event listeners.
- What you can do after
- Apply it via D3.js to resize chart text responsively and maintain readable labels on small screens.
Read how D3.js in Action, Third Edition explains font-size property →
Tiny CSS Projects
Text size is the typographic setting that determines the rendered dimensions of characters.
- How it is used
- Uses text size to establish visual hierarchy across profile cards, credit-card details, and forms.
- How deep it goes
- Works through pixel, em, and rem values in CSS declarations, plus font shorthand and adjustments alongside line height.
- Examples
- Shows a profile name and job title at different sizes and an enlarged first letter beside flowing paragraph text.
- What you can do after
- Apply it via CSS declarations to size interface text, choose relative units, and adjust oversized decorative letters.
CSS in Depth, Second Edition
The CSS font-size property specifies the size of an element's text.
- How it is used
- Uses font-size to scale text and relative component dimensions locally or across a page.
- How deep it goes
- Works through inherited em calculations, nested-size compounding, and responsive root overrides rather than treating font-size as a property-value catalog.
- Examples
- Uses a padded box, nested lists, and a panel that scales at three screen-width ranges.
- What you can do after
- Apply it via CSS to set inherited defaults, prevent nested text from shrinking, and scale relative-unit components responsively.
Read how CSS in Depth, Second Edition explains font-size property →
Design for Developers
Font size is the specified height of text glyphs in a typographic style, commonly set through CSS.
- How it is used
- Sets text scale for hierarchy, readability, responsive typography, and consistent interface spacing.
- How deep it goes
- Explains unit choice, base sizing, type ramps, and vertical-rhythm calculations, but stops short of detailed CSS implementation.
- Examples
- Uses px-to-rem conversions, heading scales, baseline grids, line-height comparisons, and browser-rendered typography.
- What you can do after
- Apply it via CSS by choosing an accessible base size, building a type ramp, and adjusting related spacing in the browser.
Read how Design for Developers explains font-size property →
Web Design Playground
A CSS property that sets the size of text.
- How it is used
- Controls text sizing while styling headings, body text, captions, sidebars, and navigation.
- How deep it goes
- Explains pixel and em values, then works through inherited relative sizing; defers the full set of CSS units.
- Examples
- Uses h1 at 36px, div text at 24px, and nested body, header, and h1 rules using em values.
- What you can do after
- Apply it via CSS rules to size text consistently and choose relative values that follow user default sizes.
Read how Web Design Playground explains font-size property →
WordPress Power Toolkit: Harness AI to build next-level websites
Font size is the typographic setting that determines the displayed height of text characters, commonly specified in pixels.
- How it is used
- Guides readable website typography choices for body text, headlines, and captions.
- How deep it goes
- Explains screen-relative pixels and practical sizing factors through WordPress controls and theme behavior.
- Examples
- Uses 16–18 px body text, thin-typeface adjustment, WordPress Typography controls, and an AI review of a pet-adoption site.
- What you can do after
- Operate WordPress typography controls to set readable text sizes and evaluate them with related spacing and typeface choices.
Web Design Playground, Second Edition
The CSS font-size property specifies the size of text rendered for an element.
- How it is used
- Controls text scale as part of deliberate CSS typography and page design.
- How deep it goes
- Defines pixel and relative sizing, inheritance, and browser defaults, while deferring the full range of CSS measurement units.
- Examples
- Demonstrates a 24px div, a default-sized paragraph, user font-size settings, and nested em calculations.
- What you can do after
- Apply font-size declarations in pixels or relative units and anticipate how defaults and inheritance affect rendered text.
Read how Web Design Playground, Second Edition explains font-size property →
Related concepts
- pixeluses · A pixel is either a discrete sample carrying visual information at a position in a digital image or a reference unit used to express rendered dimensions.
- divconfigures · The HTML div element is a generic container for grouping flow content without inherent semantic meaning or specialized behavior.
- remused by · The rem is a CSS relative length unit whose value equals the computed font size of the document’s root element.
- emused by · The em is a CSS relative length unit whose computed value is based on the applicable font size.
- headingconfigures · A heading is a textual or semantic label that introduces a section of content and, when structured, indicates its level in the document hierarchy.
These guides are generated from the text of Manning books by Manning's knowledge graph and link to the sections they draw on. The full books are available on liveBook and at manning.com.