Line Length Readability

Paste text or enter a CSS column width to instantly check whether your line lengths fall within the WCAG-recommended 45-75 characters per line range.

Tip: use real column-wrapped text for accurate results.

Paste text or use the CSS Estimator, then click Analyze.

Line Length Reference

Too short (< 45 CPL)
Choppy rhythm; uncomfortable for sustained reading.
Optimal (45-75 CPL)
Recommended by typographers and readability researchers.
Acceptable (76-80 CPL)
Within WCAG 1.4.8 AAA ceiling but above ideal.
Too long (> 80 CPL)
Fails WCAG 1.4.8 AAA; high risk of eye-tracking errors.

Summary

Paste text or enter a CSS column width to instantly check whether your line lengths fall within the WCAG-recommended 45-75 characters per line range.

How it works

  1. Paste body text into the input area — each line break counts as a separate line.
  2. The tool counts raw characters per line (including spaces) for every line.
  3. Average, minimum, maximum, and median CPL are computed and displayed.
  4. Each metric is benchmarked against the ideal range (45-75 CPL) and the WCAG 1.4.8 AAA ceiling (80 CPL).
  5. A per-line breakdown table highlights lines that are too short, optimal, or too long.
  6. Switch to the CSS estimator tab to calculate expected CPL from container width, font size, and font family.

Use cases

Frequently Asked Questions

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Last updated: 2026-05-29 · Reviewed by Nham Vu