Updated 12 October 2026 · By Abhilash Sahoo, Infyways
Legibility is how easily you can distinguish individual letters and words; readability is how easily you can read and understand the whole text. Legibility is about type design (font, size, contrast, spacing). Readability is about the writing and layout (sentence length, word choice, structure, line length). A text can be perfectly legible and still hard to read.
Legibility vs readability: what is the difference?
| Legibility | Readability | |
|---|---|---|
| Question it answers | Can I tell the characters apart? | Can I follow and understand it? |
| Controlled by | Typeface, font size, weight, letter spacing, colour contrast | Sentence and word length, vocabulary, headings, paragraphs, line length, line height |
| Owner | Type designer / UI designer | Writer, editor and layout designer |
| How to measure | Contrast ratio, minimum size, user testing | Readability formulas (Flesch, Flesch-Kincaid), user testing |
What is a readability score?
A readability score estimates how hard a text is to read, using sentence length and word length or syllables. The two most used:
- Flesch Reading Ease (0–100, higher is easier). 60–70 is plain English; most web content should aim for 60 or higher.
- Flesch-Kincaid Grade Level: the US school grade needed to understand the text. For a general audience, aim for grade 8 or below.
Tools that report them include Hemingway Editor, Yoast SEO and Rank Math (in WordPress), and the readability statistics in Microsoft Word.
How do I increase my readability score?
- Put the answer or main point first, then the detail.
- Keep sentences short: aim for an average under 20 words, and split anything over 25.
- Prefer common words to jargon; define a technical term the first time you use it.
- Write in the active voice (“we fixed the bug”, not “the bug was fixed”).
- Keep paragraphs to 2–4 sentences.
- Use question-style headings, bullet lists and tables so readers can scan.
- Cut filler words: very, really, in order to, it is important to note that.
How do I improve legibility on a website?
- Body text of at least 16px, with a line height of about 1.5.
- Text contrast of at least 4.5:1 against the background (WCAG 2.2 AA; 3:1 for large text).
- Line length of roughly 50–75 characters.
- A plain, well-hinted font for body text; save decorative fonts for headings.
- Left-aligned text rather than justified, so word spacing stays even.
Contrast and text size are also accessibility requirements; see our European Accessibility Act guide.
Does readability affect SEO?
Google does not use a readability formula as a ranking factor. But readable pages are easier for people to use and for AI answer engines to quote: a clear one-sentence answer under a question heading is exactly what gets lifted into featured snippets and AI Overviews. Treat the score as a guide, not a target.
Want content written for both readers and search engines? See our SEO content writing services.
Frequently asked questions
What is the difference between legibility and readability?
Legibility is about distinguishing letters and words (type design); readability is about understanding the text (writing and layout).
What is a good readability score?
A Flesch Reading Ease of 60 or higher, or a Flesch-Kincaid grade of about 8 or lower, suits most web content.
Is readability a Google ranking factor?
No readability formula is a ranking factor, but clear, scannable content is easier for users and AI answer engines to use.
How can I make text more legible?
Use at least 16px body text, 4.5:1 contrast, about 1.5 line height and 50–75 characters per line.