Text Readability Checker

How to use the text readability checker

1. Paste at least 100 words — the formulas are unreliable on less.
2. Read the Flesch score and the grade-level average.
3. Act on the suggestions rather than the number.

About this tool

Six formulas at once, because they disagree and the disagreement is informative. Flesch Reading Ease runs 0 to 100 with higher meaning easier; the rest report a US school grade. Where they cluster, the reading is probably right; where one is an outlier, it usually reveals something about the text — Coleman–Liau and ARI use letter counts rather than syllables, so a text full of short but unusual words scores differently on those.

It is worth being blunt about what these measure. Every one of them is a regression fitted decades ago against school grade levels, and every one reduces to sentence length and word length. None can tell whether a sentence makes sense. A page of short, random words scores as highly readable. That makes them a good check on prose that has drifted long, and a bad target to optimise against — writing to hit a score produces choppy, patronising text that scores well and reads badly.

The suggestions below the scores are the useful part. They name your longest sentence and the share of long words, because splitting the worst sentence moves every score more than any other single edit.

Syllables are estimated from spelling, with a short exception list for common words the rules get wrong. It is close on ordinary English and unreliable on names and loanwords.

Common uses

• Checking whether public-facing copy is too dense.
• Meeting a plain-English requirement for a document.
• Finding the sentences that make a draft hard going.

Frequently asked questions

What is a good Flesch Reading Ease score?

Around 60 to 70 for a general audience, which is roughly the level of a broadsheet newspaper. Below 30 is academic or professional writing.

Why do the formulas disagree?

They weight things differently — some count syllables, others count letters. Where they cluster the reading is reliable; an outlier usually says something about the vocabulary.

Can I just write to hit a score?

You can, and it produces bad writing. The formulas only measure sentence and word length, so chopping every sentence in half raises the score while making the text worse.

How accurate is the syllable counting?

Close on ordinary English, since it counts vowel groups and corrects a list of common irregulars. Names and loanwords are where it goes wrong.