W Words Counter AI
Four scores. One verdict. Privacy-first.

Readability checker — all four scores, instantly.

Flesch Reading Ease, Flesch-Kincaid Grade, Coleman-Liau and ARI — calculated in your browser as you type. With a plain-English explainer for each so you know what to do with the numbers.

Your text
Flesch Reading Ease●
—
N/A
Flesch-Kincaid Grade●
—
US Grade Level
Coleman-Liau Index●
—
US Grade Level
Automated Readability Index●
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US Grade Level

What each score actually means

Each formula measures different surface features of your text. Knowing which to trust depends on what you’re writing for.

Flesch Reading Ease (0–100)

The most common readability score. Higher is easier. The formula penalises long sentences and long words (lots of syllables). It’s the score to aim for when writing for a general web audience: 60–70 for blog posts, 70+ for marketing copy, 80+ for content aimed at younger readers. Below 30 is academic-paper territory.

Flesch-Kincaid Grade Level

Same inputs as Flesch Reading Ease, different output: a US school grade. A score of 8.0 means an 8th-grader (≈13-year-old) could read the text. The two scores move in opposite directions — easier text has a higher Flesch Reading Ease and a lower Flesch-Kincaid grade. Use this when you’re writing for a specific age group.

Coleman-Liau Index

Uses character count and sentence count instead of syllables. That makes it more reliable for text with technical terms, brand names or acronyms — anything where syllable counting gets confused. Returns a US grade level. Trust it for technical writing.

Automated Readability Index (ARI)

Like Coleman-Liau, ARI dodges syllable counting. It uses characters per word and words per sentence to estimate grade level. Originally built for the US military to test typewritten manuals, it’s well-suited to instructional and technical writing.

Which one should I trust?

For most writing on the web, lead with Flesch Reading Ease. For technical or academic writing where the prose is full of jargon, Coleman-Liau and ARI give a fairer reading. If two scores agree, you can be confident in the rating; if they diverge by more than 2 grades, your text probably has unusual structure (very short sentences, very long words, or both).

Six rules of thumb to lift readability

  • Average sentence length under 20 words; aim for 14–16 for marketing copy.
  • Vary sentence length. Two short sentences after one long one fixes most rhythm problems.
  • Replace one long word with one short one per paragraph. Stop, don’t cease. Use, don’t utilise.
  • Cut adverbs that don’t change the meaning — “really”, “very”, “quite”.
  • Read it out loud. Anything that makes you take a second breath is too long.
  • Stop chasing the score. A Flesch of 60 with clear meaning beats a 75 of mush.

Other tools

Same engine, different focus.

Word counter

The flagship tool — words, sentences, paragraphs and top-words analysis on one page.

Open word counter →

Character counter

Twitter, Instagram, LinkedIn and SMS limits with a live remaining-character indicator.

Open character counter →

Reading time calculator

Words to minutes for blog posts, scripts and presentations.

Open reading time →

Frequently asked questions

What is a good Flesch Reading Ease score?
For general web content, aim for 60–70 (around 8th-grade reading level). Marketing copy benefits from 70+. Academic writing typically lands at 30–50. Below 30 is read with significant effort.
Which readability score should I rely on?
For most web and marketing copy, lead with Flesch Reading Ease (0–100, higher is easier). For age-targeted content (textbooks, school work), use Flesch-Kincaid Grade Level. Coleman-Liau and ARI are more reliable when text contains many acronyms or technical terms because they don’t rely on syllable counting.
How accurate are readability scores?
Readability formulas are heuristics. They measure surface features (sentence length, syllables per word) rather than meaning, so they can rate clear prose as difficult if it has long sentences, or rate confusing prose as easy if its sentences are short. Use them as one signal among many.
What’s the difference between Flesch Reading Ease and Flesch-Kincaid Grade Level?
They use the same inputs (sentence length and syllables per word) but produce different scales. Flesch Reading Ease returns 0–100 with higher being easier. Flesch-Kincaid Grade Level returns a US school grade — 8.0 means an 8th-grader could read it. The two move in opposite directions: easier text means a higher Flesch Reading Ease and a lower grade level.