✍️ Hemingway Editor: Free Readability Checker & Grade Level Tool
By Shihab Mia · Updated 2026-07-26
This free Hemingway editor grades how readable your writing is and shows you exactly why, right in your browser. Paste any text and it instantly returns a reading grade level, word and sentence counts, and color-coded highlights for the five things that most often make prose hard to follow: long sentences, very long sentences, adverbs, passive voice, and weak qualifier words. It works the same way the original Hemingway App does: type or paste, read the highlights, rewrite the flagged spots, and watch the grade drop. Nothing is uploaded to a server, so it is safe to paste unpublished drafts, client emails, or work you are not ready to share.
What is the Hemingway Editor (Readability Checker)?
The Hemingway style of editing is built on one idea: clear, plain writing is easier to read and more persuasive than dense, complicated prose. Ernest Hemingway was known for short declarative sentences and strong verbs, and the free web app named after him (hemingwayapp.com) turned that style into a checklist you can run against your own text. This tool follows the same checklist. It scans your writing, computes a grade level, and marks the patterns that slow a reader down so you can fix them before you hit publish.
The headline number is a reading grade level, calculated here with the Automated Readability Index (ARI). ARI uses two things that strongly predict difficulty: how many characters your words contain on average (longer words are harder) and how many words your sentences contain on average (longer sentences are harder). The formula is ARI = 4.71 times (characters divided by words) plus 0.5 times (words divided by sentences) minus 21.43, and the result rounds to a US school grade. Worth knowing: the official Hemingway App scores text with the Flesch-Kincaid Grade Level formula instead, which weighs syllables per word rather than characters per word. The two formulas usually land within a grade or two of each other on normal prose, but they are not identical, so do not be surprised if this tool and the original app show slightly different numbers on the exact same paragraph. According to Hemingway App's own documentation, the app targets roughly a grade 9 reading level by default, since that is close to the average reading level of adults in the United States.
Beyond the grade, this checker flags five kinds of trouble, matching the categories the original app made famous. Sentences longer than 14 words are marked hard, and sentences longer than 20 words are marked very hard, because long sentences force a reader to hold more clauses in mind at once before the point lands. Adverbs ending in -ly are flagged because a strong verb is usually better than a weak verb plus an adverb ("sprinted" beats "ran quickly"). Passive voice, a form of "to be" plus a past participle such as "was written", is flagged because the active voice is usually shorter and names who did what. Qualifier and filler words like "very", "really", "just", "quite", "basically", and "actually" are flagged because they pad a sentence without adding meaning.
All of this analysis happens client-side, meaning the JavaScript running in your own browser tab does the counting and pattern matching. Your text is never sent to a server, logged, or stored, which matters if you are editing a manuscript, a legal draft, or anything under embargo. There is no login, no file upload, and no character limit tied to a paid tier; you can paste a full blog post or a whole chapter and get results instantly, then keep editing and re-checking as many times as you like.
These checks are heuristics, not grammar rules, so treat every highlight as a suggestion rather than a command. A long sentence can be perfectly clear, the passive voice is sometimes the right choice, and a single adverb rarely ruins a paragraph. The goal is awareness: when a paragraph lights up with color, that is a signal to read it aloud and ask whether a reader would stay with you to the end. Use the counts to spot habits across a whole document rather than obsessing over any single flagged word, and your writing will read faster and land harder.
Writers reach for a Hemingway-style checker at different stages. Some run a first draft through it to see where their default sentence length sits, then edit toward a target grade for their audience. Others use it as a final pass before publishing, treating a spike in red (very hard) sentences or a cluster of passive voice as a checklist item before the piece goes live. Either way, the tool works best paired with reading your text out loud; a checker catches patterns, but your own ear still catches tone, rhythm, and whether the piece actually sounds like you.
When to use it
- Tightening a blog post, essay, or report so it reads at a grade 9 level or below before publishing.
- Catching passive voice and filler words in cover letters, emails, and product copy before you hit send.
- Helping students and ESL writers see which sentences run too long and how to split them.
- Editing marketing and UX copy where short, punchy sentences convert better than dense paragraphs.
- Auditing a novel chapter or short story draft for adverb overuse before sending it to an editor or beta reader.
- Checking a press release or company blog post against a consistent, plain-language house style.
How to use the Hemingway Editor (Readability Checker)
- Paste or type your text into the box, or click "Load sample text" to see a worked example.
- Read the grade level and the plain-English summary to gauge overall difficulty at a glance.
- Scan the colored highlights: amber for hard sentences, rose for very hard, sky blue for adverbs, violet for passive voice, and teal for qualifiers.
- Rewrite the highlighted spots one at a time, shorten long sentences, and watch the grade and counts update live as you edit.
- Click Copy text once you are happy, and paste the cleaned-up version into your document or CMS.
Formula & method
Worked examples
Grading a short, simple sentence: "The dog ran home fast." (5 words, 17 letters and digits).
- characters per word = 17 / 5 = 3.4.
- words per sentence = 5 / 1 = 5.
- ARI = 4.71 * 3.4 + 0.5 * 5 - 21.43 = 16.01 + 2.5 - 21.43 = -2.92.
- A negative result floors to grade 1.
Result: Grade 1: very easy to read, exactly the kind of short, plain sentence the Hemingway style rewards.
Flagging a wordy sentence: "The report was carefully reviewed by the committee before it was finally approved." (13 words).
- Count the words: 13, which is under 14, so it is not yet marked hard for length.
- "was reviewed" and "was approved" are a "be" verb plus an -ed participle, so passive voice is flagged twice.
- "carefully" and "finally" end in -ly, so two adverbs are flagged.
- Rewrite active and lean: "The committee reviewed the report, then approved it."
Result: The rewrite drops to 8 words, removes both passive constructions and both adverbs, and reads at a lower grade.
A 34-word run-on sentence stuffed with qualifiers: "It was really quite obvious that the team, which had basically been working on the project for months, was actually going to need considerably more time than everyone had originally and very optimistically expected."
- Word count is 34, which is well over the 20-word threshold, so the whole sentence is marked very hard.
- "really", "quite", "basically", and "actually" are all qualifiers, four flags in one sentence.
- "optimistically" ends in -ly and is flagged as an adverb.
- Split it: "The team had worked on the project for months. It needed far more time than everyone expected."
Result: Two short sentences replace one very hard, qualifier-heavy sentence, cutting the word count by more than half.
Reading grade levels and what they mean for your audience
| ARI grade | Reader | Verdict |
|---|---|---|
| 1 to 6 | Up to grade 6 | Very easy, great for broad and mobile audiences |
| 7 to 9 | Grade 7 to 9 | Good, the target for most web writing and roughly the US adult average |
| 10 to 12 | High school | Fairly hard, aim a little simpler |
| 13 to 15 | College | Hard, shorten sentences and cut jargon |
| 16 and up | Graduate | Very hard, simplify before publishing |
What this tool highlights and why it matters
| Flag | Trigger | Quick fix |
|---|---|---|
| Hard sentence | More than 14 words | Split it into two shorter sentences |
| Very hard sentence | More than 20 words | Cut clauses or break into several sentences |
| Adverb | Word ending in -ly | Swap weak verb plus adverb for one strong verb |
| Passive voice | Form of "to be" plus an -ed verb | Name the doer and use an active verb |
| Qualifier | very, really, just, quite, basically, actually | Delete it; the sentence rarely loses meaning |
This tool vs. the original Hemingway App
| Feature | This tool | Original Hemingway App (hemingwayapp.com) |
|---|---|---|
| Grade formula | Automated Readability Index (ARI) | Flesch-Kincaid Grade Level |
| Cost | Free, no account | Web version free; Editor Plus desktop app is paid |
| Data sent to a server | None, runs fully client-side | Free web checker also runs client-side |
| Highlights | Hard, very hard, adverb, passive, qualifier | Same five, plus purple "complicated phrase" suggestions in the full app |
| Export / formatting | Copy plain text | Rich text export in the paid desktop app |
Common mistakes to avoid
- Treating the grade level as a hard rule. A grade 9 target suits general audiences, but technical, legal, or academic writing can sit higher and still be correct. Use the grade as a guide, not a pass-fail test, and judge each piece against its real readers.
- Removing every passive sentence. The passive voice is the right choice when the doer is unknown or unimportant, as in "the bridge was built in 1890". Fix passive voice only when naming the actor makes the sentence clearer or shorter.
- Deleting all adverbs on sight. The flag points out a habit, not an error. A single well-chosen adverb is fine. The win comes from replacing weak verb plus adverb pairs like "walked slowly" with one vivid verb like "trudged".
- Confusing characters with words in the formula. ARI divides characters by words, not the other way around. Counting whole words where the formula wants letters, or vice versa, gives a wildly wrong grade. This tool counts letters and digits as characters for the grade.
- Expecting an identical score to the official Hemingway App. This tool uses the Automated Readability Index while hemingwayapp.com uses Flesch-Kincaid Grade Level. Both are legitimate, widely used formulas, but they weigh word and sentence length slightly differently, so a small gap between the two scores on the same text is expected and not an error.
- Editing sentence by sentence without reading the whole piece aloud. A checker catches word and sentence patterns, not tone, rhythm, or whether an idea actually makes sense in context. Always read the final draft out loud after clearing the highlights; it catches problems no automated grade level can.
Glossary
- Readability
- How easy a piece of text is to read and understand, usually expressed as a school grade level.
- Automated Readability Index (ARI)
- A formula that estimates reading grade from average word length (characters per word) and average sentence length (words per sentence). Used by this tool.
- Flesch-Kincaid Grade Level
- A different readability formula, based on syllables per word and words per sentence, used by the official Hemingway App and Microsoft Word.
- Passive voice
- A sentence where the subject receives the action, formed with a "to be" verb plus a past participle, such as "the cake was eaten".
- Adverb
- A word that modifies a verb, adjective, or other adverb; many end in -ly and can often be replaced by a stronger verb.
- Qualifier
- A filler word such as "very", "really", or "just" that weakens a statement without adding real meaning.
- Reading time
- An estimate of how long the text takes to read, here based on an average pace of 250 words per minute.
- Hard sentence / very hard sentence
- This tool's labels for sentences over 14 words (hard) or over 20 words (very hard), the lengths most likely to slow a reader down.
Frequently asked questions
What is a Hemingway editor?
A Hemingway editor is a readability tool that grades your writing and highlights what makes it hard to read, such as long sentences, passive voice, adverbs, and filler words. It is named after Ernest Hemingway, known for short, plain, direct prose, and it mirrors the free checker at hemingwayapp.com.
Is this the same as the official Hemingway App?
No, this is an independent tool inspired by the same editing style. It flags the same five categories of issues, but it calculates the grade level with the Automated Readability Index rather than the Flesch-Kincaid formula the official app uses, so scores on identical text can differ by a grade or two.
What reading grade level should I aim for?
For general web writing, aim for grade 9 or below so a wide audience can follow you easily; that is roughly the average adult reading level in the United States. Technical or academic work can run higher, but if a piece scores grade 13 or more, look for long sentences and jargon to trim.
How is the grade level calculated?
It uses the Automated Readability Index: 4.71 times the average characters per word, plus 0.5 times the average words per sentence, minus 21.43. The result rounds to a US school grade, so longer words and longer sentences push the grade up.
Why is a sentence marked hard or very hard?
A sentence is marked hard when it runs longer than 14 words and very hard when it runs longer than 20. Long sentences make readers hold more in mind at once, so splitting them usually improves clarity.
Is passive voice always wrong?
No. The passive voice is fine when the doer is unknown or beside the point, like "the law was passed in 2020". The tool flags it so you can check whether an active version would be shorter and clearer, not because it is always a mistake.
Does this tool check grammar and spelling too?
No. This is a readability and style checker, not a grammar or spelling checker. It focuses on sentence length, passive voice, adverbs, and qualifiers; pair it with a dedicated grammar checker if you also need spelling and punctuation fixes.
How many adverbs or passive sentences is too many?
There is no fixed limit, but if adverbs or passive voice are flagged in most of your sentences, that usually signals a habit worth breaking. Aim to notice the pattern across a whole page rather than trying to hit zero on any single count.
Can I use this for academic or technical writing?
Yes, but expect and accept a higher grade level. Academic and technical writing often needs precise, multi-syllable vocabulary that a general-audience checker will flag; use the highlights to catch genuinely bloated sentences rather than to force plain-English scores on specialist content.
Is my text private?
Yes. All analysis runs in your browser with JavaScript and nothing is sent to a server. Your text never leaves your device, so it is safe to paste drafts, emails, manuscripts, and unpublished work.
Sources
- What a Readability Score is and how to use it in your writing , Hemingway App
- Readability and document stats , Hemingway App Help