WEBSITE & CONVERSION

Website Readability & Clarity Checker

Paste a URL and get six real readability formulas — Flesch, Flesch-Kincaid, Gunning Fog, SMOG, Coleman-Liau, and ARI — computed from the page's actual text, plus the exact sentences dragging your score down.

Works best on content-heavy pages — a blog post, docs page, or marketing page with real paragraphs.

Readability Engineering Guide

The 6 Formulas, Explained

Every score below comes from real, published readability research — not a proprietary black box. Each formula weighs sentence length and word complexity slightly differently, which is why we show all six instead of picking a favorite.

Flesch Reading Ease

The most widely cited readability score, 0-100 (higher = easier). Combines average sentence length and average syllables per word. 60-70 is considered plain, everyday English.

Flesch-Kincaid Grade Level

The same underlying math as Reading Ease, rescaled to a U.S. school grade level. A score of 8 means the text is readable by an average 8th grader.

Gunning Fog Index

Weighs 'complex words' (3+ syllables) more heavily than the Flesch formulas. It's the strictest of the six on jargon-heavy writing.

SMOG Index

Designed for health and safety writing where comprehension really matters. Estimates the years of education needed to fully understand the text, based purely on complex-word density.

Coleman-Liau Index

Uses characters per word instead of syllables, which makes it easy to compute reliably (syllable counting is always a heuristic) and less sensitive to unusual word choices.

Automated Readability Index (ARI)

Similar to Coleman-Liau — character-based rather than syllable-based — originally designed for real-time readability scoring on typewriters and early computers.

The Flesch Reading Ease Scale

90-100Very Easy5th grade
80-89Easy6th grade
70-79Fairly Easy7th grade
60-69Standard8th-9th grade
50-59Fairly Difficult10th-12th grade
30-49DifficultCollege
0-29Very ConfusingCollege graduate

Known Limitations

  • Syllable counting uses a vowel-group heuristic, not a dictionary — it's accurate for the vast majority of English words but can be off by one syllable on unusual spellings. This averages out over a full page of text.
  • Sentence splitting relies on punctuation and capitalization cues. It correctly handles common abbreviations (Dr., Mr., etc., vs., e.g.) and decimal numbers, but unusual formatting can occasionally cause a mis-split.
  • Like the Dashboard UX Analyzer, this tool only sees the raw server-rendered HTML — client-rendered pages that inject their text via JavaScript will show as low word count.

Frequently Asked Questions

What reading level should my SaaS website target?

Most high-converting B2B SaaS marketing copy targets a 6th-8.5th grade level — plain, direct language. This holds even for technical, expert audiences: simpler writing reads faster and converts better, it doesn't signal a lack of sophistication.

Why do the six scores disagree with each other?

Each formula was developed independently, for different purposes (Flesch for general text, SMOG for health literacy, ARI for real-time computation) and weighs sentence length vs. word complexity differently. Use the average, and treat any single score as one data point.

My score seems low but my writing feels simple — why?

Check the 'Sentences Dragging Your Score Down' list. A handful of very long sentences (25+ words) can pull down an otherwise simple page's score more than you'd expect, since all six formulas weight sentence length heavily.

Does this analyze the whole site or just one page?

One URL at a time. Run it against your highest-traffic pages individually — homepage, top blog posts, pricing page — since readability can vary a lot page to page.

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