Before you hand students a reading, it helps to know roughly how hard it reads. This checker applies two classic readability formulas to any text you paste and marks the sentences that run long, since long sentences are usually the quickest thing to fix. It is a rough guide, not a verdict, and the notes below say where it goes wrong. Nothing you type leaves your browser, so you can paste student writing or unpublished material without it going anywhere.
Check a passage
Paste at least a few sentences. Very short samples give unstable scores.
How to use it
Paste a passage
A few paragraphs works better than a single line. Leave out headings, captions and answer choices, which have no sentences to measure.
Read both scores
The grade level is a US grade estimate. Reading ease runs the other way: higher is easier. They are built from the same two inputs, sentence length and syllables per word, so they usually agree.
Look at the marked sentences
Long sentences are highlighted, and also listed below with their word counts so you can find them without relying on colour.
Edit and recheck
Split one long sentence into two and the score drops quickly. Swapping hard words for plain ones lowers it too, but only the formula notices.
What readability formulas can and cannot tell you
Both formulas look at only two things: how long the sentences are and how long the words are. That is a crude stand-in for difficulty. A sentence of short words can still be about ideas students have never met, and a passage full of long, familiar words, like "information" or "everybody", scores harder than it reads. Poems, lists, dialogue and anything with unusual punctuation confuse the sentence count, and the syllable counter is a rule of thumb that misses plenty of words. Scores from different tools differ for the same text for these reasons. Use the number as a prompt to read the passage again with your students in mind, not as a label for a child or a text.
What to do with a passage that is too hard? You can shorten the sentences, define the key terms before reading, or read it aloud together. The pages on differentiated instruction and scaffolding go through those moves, and universal design for learning explains why offering a text in more than one form helps the whole room. If students in the same class read at very different levels, mixed-ability classrooms has some starting points.
Do not use it to rank students. This tool measures text, not people. A grade-level score for a passage does not say what a particular reader can handle with support, background knowledge or interest.
How it compares with ClassSense
ClassSense does not report reading level. It builds skill packs from a unit you upload, with an explanation at three depths, and it has Learning Supports a teacher can switch on for a student, such as read-aloud with word highlighting, larger text, more spacing and a colour overlay. Those supports change how a student reads the material, not the measured difficulty of the text, and they are not a diagnosis of anything. If you want a number for a passage before you use it, this page gives you a rough one. See read-aloud and accommodations for what the supports do. Your first 30 days are free, no card.
Common questions
What is the Flesch-Kincaid grade level?
A formula that estimates a US school grade from average sentence length and average syllables per word. A result of 7 means the text is roughly what a student in the seventh grade could be expected to read. It is an estimate only.
What does Flesch reading ease mean?
A score from the same two inputs where higher means easier. Plain English sits in the 60s and 70s. Dense academic writing is often below 30. Scores can fall outside zero to one hundred for unusual text.
Why does my passage score differently in another tool?
Tools split sentences and count syllables in slightly different ways, especially around abbreviations, numbers and hyphenated words. The differences are usually small, but they are real.
Is my text uploaded anywhere?
No. Everything is calculated in your browser. There are no network calls and nothing is stored, so closing the tab discards your text.