Line length
Line length is the amount of text occupying one line, commonly measured by character count or rendered horizontal width.
Web Design Playground, Second Edition
Line length is the number of characters displayed on a single line of text.
- How it is used
- Uses text-block width to make body copy easier to scan on screens.
- How deep it goes
- Explains a practical character range and adjusts CSS width and font size, without detailing font metrics.
- Examples
- Uses a 550px body and a 630px div to shorten overly wide paragraph lines.
- What you can do after
- Apply it via CSS width and font-size changes to bring body text into a readable range.
Read how Web Design Playground, Second Edition explains line length →
Web Design Playground
The measure of how many characters or how much text fits on one line before wrapping.
- How it is used
- Uses text-container width to keep screen paragraphs comfortable to scan.
- How deep it goes
- Explains character-per-line targets and width adjustments, then applies them to responsive breakpoint choices.
- Examples
- Uses a 150-plus-character paragraph, 400px and 600px containers, and a 550px media-query breakpoint.
- What you can do after
- Apply it via CSS width and media queries to keep text lines within a readable range.
Design for Developers
Line length is the amount of text, commonly measured in characters, spanning one line of a text block.
- How it is used
- Improves web readability by guiding text-column width and helping users scan and focus on written content.
- How deep it goes
- Defines a 45–70-character guideline and implementation choices, but stops short of detailed readability research or measurement methods.
- Examples
- Uses web paragraphs, headings, constrained columns, and comparisons of long text blocks to illustrate readable proportions.
- What you can do after
- Apply it via CSS by constraining text widths and reviewing the result with typography and user-readability checks.
Everyday Data Visualization
Line length is the horizontal extent of a line of text measured by its characters or rendered width.
- How it is used
- Improves readability, eye tracking, and accessibility in visualizations and other text-heavy interfaces.
- How deep it goes
- Explains perceptual rationale and practical trade-offs, but does not provide a specific numeric line-length limit.
- Examples
- Uses visualization text, dense reading layouts, spreadsheets, and business-intelligence tools as practical contexts.
- What you can do after
- Evaluate and adjust text layouts by shortening lines and coordinating line, paragraph, and word spacing.
Related concepts
- widthconfigured by · Width is a measure of extent along a specified dimension, such as spatial size or the number of units or features in a model.
- font-size propertyconfigured by · The CSS font-size property specifies the nominal size of an element’s rendered text.
- code readabilitymeasures · Code readability is the ease with which human readers can perceive and understand source code, including its structure and intent.
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