Readability Checker

It scores your writing with two standard readability formulas, Flesch Reading Ease and Flesch-Kincaid Grade Level, and shows where your writing gets dense. You can upload a Word document or paste text, and you get an overall score, a per-paragraph heatmap that colors your text from easy to difficult, a list of your five densest paragraphs, and the option to score any paragraph or highlighted selection on its own.

Flesch Reading Ease rates how easy a text is to read on a scale from 0 to 100. Higher scores mean easier writing. The formula uses two things: how long your sentences are on average, and how many syllables your words have on average. The usual bands:

• 90 and above: Very easy. Around 5th grade.
• 80 to 89: Easy. Around 6th grade.
• 70 to 79: Fairly easy. Around 7th grade.
• 60 to 69: Standard. Around 8th to 9th grade. Plain English aimed at most adult readers lives here.
• 50 to 59: Fairly difficult. Around 10th to 12th grade.
• 30 to 49: Difficult. College level.
• Below 30: Very difficult. College graduate level.

The Flesch-Kincaid Grade Level translates readability into a US school grade. A score of 8.4 means the text should be understandable to an average eighth grader, and 13 means college level. It is built from the same two ingredients as Reading Ease, average sentence length and average syllables per word, so the way to lower it is the same: shorter sentences and simpler words where the meaning allows.

It depends on who is reading. For general audiences, aim for 60 to 70, the standard band that most adult readers are comfortable with; this is the range plain-language guides usually recommend for websites, reports, and public communication. Academic papers, legal documents, and technical manuals legitimately score lower because their vocabulary is specialized, so a research paper landing in the fairly difficult band is not automatically a problem. Match the score to the audience, not to an arbitrary target.

Because Flesch-Kincaid was designed for general English prose, and academic writing breaks its assumptions. Technical terms carry many syllables, sentences carry citations and qualifiers, and a low score follows. That does not mean the writing is bad: a methods section written for experts is supposed to be dense. Use the score to find the sentences that are dense for no reason, for example a 40-word sentence that could be two sentences, and leave necessary technical vocabulary alone. Do not oversimplify meaning to chase a number.

Most gains come from a few simple habits:

• Shorten sentences. If a sentence runs past about 25 words, look for a natural place to split it.
• Prefer common words. Use "use" instead of "utilize" where the meaning allows.
• Split dense paragraphs. A paragraph covering three ideas is easier to read as two or three paragraphs.
• Start with the worst spots. Use the heatmap and the densest-paragraphs list to fix the reddest text first.
• Keep technical terms. Replace jargon only when a plain word means the same thing; never trade precision for points.

Then re-check the document to see the score move.

Every paragraph in your document is colored by its own score: green for fairly easy and above, lime for standard, amber for difficult, and red for the very difficult band. Click any paragraph to see its exact scores. Paragraphs shown in gray are not scored reliably: headings are excluded from scoring, and paragraphs with fewer than three sentences are too short for a meaningful estimate.

Yes. Click a paragraph in the document preview to get its full scores in the side panel, or highlight any stretch of text to score just that selection, for example a single abstract or one tricky paragraph. This is useful for checking a section you just rewrote without re-reading the whole report.

Yes. The analysis scope control can exclude everything from a chosen section onward, with a one-click option to exclude the references section. This matters because reference lists are full of titles and journal names that are not meant to be readable prose, and they drag the overall score down. Headings are always excluded automatically, and the word and character counts still cover the whole document.

Word documents (.docx) or plain pasted text, whichever is convenient. If your paper is in Google Docs, use File, then Download, then Microsoft Word (.docx). If it is in Apple Pages, use the export to Word option. PDFs are not supported, because the checker needs to read the structure of the document, so export or copy your text first.

Yes, this readability checker is completely free. There is no sign-up, no account, no credit card, and no limit on how many documents or snippets you can score. It works as a free readability checker for students, researchers, editors, and anyone writing a paper, report, or website copy who wants to know how hard their text is to read. Upload a file or paste text and see your scores in seconds.

No. The whole analysis runs in your browser. Uploaded files are opened locally with JavaScript and pasted text never leaves the page, so nothing is sent to a server and nothing is stored. Close the tab and it is gone.

The formulas are standard, but the syllable counts are algorithmic estimates rather than dictionary lookups, so they can be slightly off for uncommon words, proper nouns, and technical terminology. Treat the scores as a guide for revising, not a verdict on quality: two well-written texts for different audiences can score very differently. The heatmap is most useful for spotting relative differences, the paragraphs that are much denser than the rest of your document.