Readability: Flesch Reading Ease for Web Pages
Readability is how much effort a reader needs to understand a text. For web pages it is usually estimated with the Flesch Reading Ease formula, which looks at two things only: how long the sentences are and how many syllables the words have.
206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words)
The result runs roughly from 0 to 100. Higher means easier.
| Score | Reads as |
|---|---|
| 80–100 | easy (short sentences, everyday words) |
| 60–79 | plain English, fine for most audiences |
| 50–59 | fairly difficult |
| 30–49 | difficult (academic or technical writing) |
| 0–29 | very difficult |
Why it matters
People skim web pages. Long sentences full of long words slow them down, and many leave before they reach the point. Clear text helps visitors find what they came for, which shows in time on page, sign-ups and support questions.
Readability is not a Google ranking factor in itself, and no score will rank a page. But Google’s guidance on helpful content asks whether a page is easy to read and well organised, and AI answers tend to quote passages that state one idea clearly. Clear writing helps both.
A score is a rough guide, not a verdict. Technical documentation for specialists can score low and still be right for its readers.
What we check
We read the visible text of the page as your server returns it. Each paragraph, list item, table cell and heading counts as its own block, so a heading without a full stop doesn’t merge with the next sentence. Navigation and footer text are left out.
| Result | When |
|---|---|
| Pass | Flesch Reading Ease is 50 or more |
| Needs attention | the score is below 50 |
| Info | the page isn’t in English, or has fewer than 100 words |
The formula was built for English: other languages have different word and syllable lengths, so we show word and sentence counts for them but no score. We also report the average sentence length and the share of sentences longer than 25 words. Syllables are estimated from vowel groups, which is accurate enough for a page-level score. This check informs; it doesn’t change the SEO score.
How to improve it
- Shorten long sentences. Split sentences over about 25 words. One sentence, one idea.
- Prefer common words. “Use” instead of “utilise”, “help” instead of “facilitate”. Keep technical terms your readers need, and explain them once.
- Use lists for steps and options. A numbered list is easier to follow than a paragraph of “first … then … after that”.
- Put the point first. Start sections with the answer, then the detail.
- Break up walls of text. Short paragraphs and descriptive subheadings help readers scan. See Headings and the H1 tag.
- Write in the active voice. “We check the certificate” is shorter and clearer than “the certificate is checked by us”.
Don’t chase a number by chopping every sentence into fragments: read the result aloud. If it sounds natural and a newcomer to the topic would follow it, it is readable.
For text that should also work well in AI answers, see content AI assistants can read.