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AI Essay Checker — free pre-Turnitin scan with sentence evidence.

Most universities now run every submission through an AI check before a human ever reads it. A flag at 20 percent can mean a referral, a meeting, or worse. The fix is not to hope your essay reads human, it is to check your own draft first, see which sentences flag, and rewrite the specific lines that read AI. TextSight does that in around 30 seconds: paste up to 5,000 characters, get an Authenticity Score, sentence-level highlights for every flagged line, Plagiarism Risk, and a one-click AI rewriter if you want to fix the red lines without rewriting from scratch. Free tier, no signup needed for your first scan, 3 scans every day.

Score my essay free See the 4-step workflow
3 scans/day free 5,000 chars per scan Sentence-level evidence
What the free tier includes

All three scoring modes, sentence highlights, no signup wall.

The free tier is built for the actual student workflow, not a teaser. You get every detection mode and the same sentence-level evidence paid users get. The paywall is volume, not features.

3 scans every day, 5,000 characters per scan

That covers a standard 800-word college essay plus a revision pass before you submit. The free quota resets at midnight UTC, so a busy assignment week with three classes is still inside the free band as long as each draft fits a single scan. No card, no email collection, no progress lock. If you write longer than 5,000 characters in one go, split the essay into two scans or upgrade to Pro for 10,000 characters per scan.

All three detection modes in every scan

Every scan returns the Authenticity Score on a 0 to 100 scale, the AI likelihood band, and the Plagiarism Risk score in the same pass. You do not have to pick a mode or upgrade for the second score: a single click runs all three so you see whether the essay is failing on AI-style cadence, soft plagiarism patterns, or both. Most student drafts only have one of those two problems, but knowing which one drives the score is what makes the revision targeted instead of guessed.

Sentence-level highlights for every flagged line

This is the difference between a number and a fix. Every flagged sentence is colour-coded green, amber, or red, and clicking a flag tells you the reason: AI-style cadence, stock phrasing, uncited specific, or stock textbook definition. You know which line to rewrite and why. The free tier ships the full highlight set, not a paywalled preview.

Calibrated formats

Five essay types, five different ways AI leaks through.

An AI detector that scores every essay the same way misses format-specific tells. TextSight detects the format first, then weights the signal that actually betrays AI in that format.

The five-paragraph essay

The skeleton is the tell. Intro with three signposted claims, three body paragraphs with topic sentence plus three supporting points, conclusion that restates the thesis. A real student writing this format breaks the symmetry: one body paragraph runs long, another lands a memorable line, the conclusion drifts. AI almost never breaks the skeleton. The checker weights template uniformity heavily on this format so a too-perfect structure flags even with otherwise human prose.

The argumentative essay

The hedging gives it away. Uniform hedge density, "many scholars argue", "it can be argued that", every claim wrapped in the same modal verb. Human writers vary their commitment level paragraph to paragraph; AI flattens the register. The checker tracks hedge frequency and modal-verb variance, then weights both higher when it detects argumentative scaffolding.

The comparison and contrast essay

The symmetry is the tell. AI writes comparison essays with mathematically clean parallel structure: each side gets exactly the same number of supporting points, presented in identical order. Human writers play favourites or run long on whichever side they care about more. Perfect parallelism on a comparison essay is one of the strongest single-signal flags.

The persuasive essay

Generic activist register is the tell. "We must act now", "the time has come", "society must come together". Pulled from RLHF training that rewards safe persuasive tone. Real student persuasive writing names specific actors, specific policies, specific costs. The checker flags the generic register pattern and treats specificity as the human signal.

The short narrative essay

Missing sensory detail is the tell. AI narrative defaults to event sequencing and emotion labels: "I felt happy. Then I felt sad." Human narrative anchors in physical detail: the smell of the room, the colour of the light, what someone was wearing. The checker weights sensory-density on detected narrative paragraphs, and a flat emotion-label narrative flags hard even if the grammar is clean.

Plans & pricing

Free covers a normal essay. Pro covers a heavy assignment week.

Free includes 3 scans a day with all three detection modes and sentence highlights bundled in. Paid tiers raise the per-scan character limit and add file upload, the Chrome extension, and the REST API. Yearly billing saves 25%. Students with a .edu email get Pro at $13.99/mo.

Starter
$7.49/month

Billed $89.88/year — Save $30

For 3 to 5 essays a week.
  • 20 scans/day
  • 10,000 chars per scan
  • Chrome extension
  • Full scan history
Get Starter
Pro
$14.99/month

Billed $179.88/year — Save $60

.edu email gets it at $13.99.
  • Unlimited scans
  • 50,000 AI rewriter words/mo
  • File & URL upload
  • Advanced AI rewriter modes
Get Pro
Business
$29.99/month

Billed $359.88/year — Save $120

For writing centres and tutoring programs.
  • 150,000 AI rewriter words/mo
  • REST API access
  • 5 team seats
  • Bulk CSV upload
Get Business

Students with a .edu email get Pro at $13.99/mo instead of $19.99. View full pricing

Four steps

Paste, scan, review highlights, then revise.

The whole loop runs in around 15 minutes for a standard essay. The point is to make it fast enough that you actually do it the night before submission instead of skipping it.

Step 1: Paste your essay

Open the scanner and paste up to 5,000 characters on the free tier, around 800 words. That fits most college essay assignments in a single scan. No signup is required for the first scan; the daily quota resets at midnight UTC. If your essay runs longer, split into two sections or upgrade to Pro for 10,000 characters per scan plus PDF and DOCX upload.

Step 2: Run the scan

One click runs AI detection, Authenticity Score, Plagiarism Risk, and citation parsing in the same pass. Results land in around 30 seconds for a standard essay. The result panel shows three score gauges side by side plus the full sentence-level colour map underneath. No mode picker, no upsell screen between paste and result, no "verify your email to see your score" wall.

Step 3: Review the highlights

The colour map is the actionable part of the scan. Green sentences read human. Amber sentences are borderline. Red sentences read strongly AI to the classifier. Click into any flagged sentence to see the reason: AI-style cadence, stock phrasing, uncited specific, or stock textbook definition. You always know which line to work on and why, and you can keep sentences you wrote even if they happen to land in the AI pattern.

Step 4: Revise and re-scan

For each red sentence you have three choices: edit it yourself, click Rewrite and let the tool rewrite it for you, or cut it if it was filler. Re-scan to confirm the score moved into the safe band (70 plus for graded work, 80 plus if you want margin). Most essays clear in one revision pass. A heavily AI-assisted draft might need two. The Starter and Pro tiers exist for exactly this rhythm of scan-revise-rescan across multiple drafts.

ESL fairness

Roughly 40 percent fewer false positives on non-native English.

The hidden tax most AI detectors charge: they over-flag essays from non-native English writers because formal ESL prose patterns overlap with what detectors learn from AI output. TextSight is calibrated against an ESL writing sample so the score is gentler for you, not stricter.

Why most detectors mis-flag ESL writers

Formal English-as-a-second-language prose is structurally clean: precise grammar, balanced sentence length, careful vocabulary, controlled hedge density. Those are exactly the patterns AI defaults to as well, because both were trained on the same kind of formal source material. A detector tuned only on native-speaker writing reads ESL prose as AI and flags it hard. Indian, Filipino, Nigerian, and Chinese students see this constantly, and the penalty for being a good writer in your second language ends up being an academic misconduct meeting.

How the TextSight calibration works

The classifier is trained against a dedicated ESL writing corpus alongside native-speaker text, and the sentence-level evidence layer exposes which signals fired. An ESL student can keep clean structured paragraphs that an averaging detector would mark red, because the highlight panel shows that the flag was triggered by sentence-length uniformity, not by genuine AI cadence. In our internal evals, the calibration returns roughly 40 percent fewer false positives on non-native English than the average competitor. The Authenticity Score reflects this calibration on every tier including free.

What to do if a sentence still flags

Click into the flag and read the reason. If the trigger was sentence-length uniformity, vary the lengths in that paragraph: one short sentence, one long, one medium. If the trigger was hedge density, drop one of the modal verbs and commit to the claim directly. If the trigger was generic register, swap one stock phrasing for a specific detail from the source you are discussing. None of these changes require sounding less academic, only sounding more like you.

Honest scope

TextSight is the dress rehearsal, not the replacement.

Turnitin runs inside your university submission system after you hand the essay in. TextSight runs on your own draft before. Both have a role, and the honest workflow uses them in that order.

Turnitin: the institutional gate

Turnitin runs its own AI classifier inside the submission portal your university or college uses. You do not choose when it scans, you do not see the per-sentence breakdown, and you do not get a chance to revise once the report exists. The score lands on your professor first, and by then the conversation has already shifted from your essay to your integrity. Turnitin is doing the job your institution asked it to do; the problem is that you only see the result after the only useful editing window has closed.

TextSight: the pre-submission scan

TextSight runs on your own draft, on your own laptop, before any submission portal sees the file. You see the same kind of score, plus the sentence-level evidence Turnitin does not show you, plus a built-in rewriting option for the flagged lines. The Authenticity Score correlates with Turnitin within roughly 5 to 10 percentage points in our internal testing, so a green TextSight result is a strong signal you will pass the Turnitin pass cleanly. Use TextSight to revise, then submit, then let Turnitin do its job knowing your essay reads human to a machine.

Pair both, do not replace either

The honest setup is to run TextSight on every meaningful draft during writing and let Turnitin do the final certification at submission time. That is the same pattern most professional writers settle into: a lightweight continuous tool for iteration plus a heavier final check at the gate. Three jobs, two tools, no pretence that either one replaces the other.

FAQ

AI essay checker, frequently asked.

Is the AI essay checker really free?
Yes. The free tier includes 3 scans every day with no card and no signup. Each scan returns the AI score, the Authenticity Score, sentence-level highlights, and Plagiarism Risk in the same pass, up to 5,000 characters per scan. That is enough for a standard 800-word college essay plus one revision pass.
Will TextSight match what Turnitin shows my professor?
Not exactly, but close. Turnitin runs its own classifier and reports a separate percentage after submission. The TextSight Authenticity Score correlates with Turnitin within roughly 5 to 10 percentage points in our internal testing. Treat TextSight as the pre-submission draft check, not as Turnitin itself. The point is to catch sentences that need revision before your professor sees the report.
I am a non-native English writer. Will the checker flag me unfairly?
AI detectors have a documented false-positive bias against ESL writers because non-native prose patterns overlap with what detectors learn from AI output. TextSight is calibrated against an ESL writing sample and returns roughly 40 percent fewer false positives on non-native English than the average competitor in our internal evals. The score is gentler for you, not stricter, and the sentence highlights help separate genuine AI register leakage from second-language prose patterns.
Which essay formats does the checker calibrate for?
Five formats: five-paragraph essays, argumentative essays, comparison and contrast essays, persuasive essays, and short narrative essays. Each format leaks AI through a different signal, so the checker weights the relevant pattern more heavily once the format is detected. That is why a clean five-paragraph essay can still flag if the AI-typical topic-sentence skeleton is too perfect.
Does TextSight tell my school or report me if it finds AI?
No. Every scan is private to your account and is never shared with universities, schools, or any third party. Teachers cannot view your scan history even if they ask. The only way a teacher sees a TextSight report is if you choose to export a PDF and hand it to them yourself, which is the same model Grammarly uses.
Can I check an essay longer than 5,000 characters?
Free tier caps at 5,000 characters per scan, which is around 800 words. For longer essays you have two options. Either split the essay into two sections and scan each one, which is fine for catching flagged paragraphs. Or upgrade to Pro for 10,000 characters per scan plus file and URL upload, which makes the workflow much faster on dissertation chapters and long-form assignments.
Do you offer a student discount?
Yes. Students with a verified .edu email get Pro at 13.99 USD per month instead of the standard 19.99. That includes unlimited scans, 10,000 characters per scan, 50,000 AI rewriter words per month, file upload, and the advanced AI rewriter modes. The discount is applied automatically at signup once the email is verified, no waiting and no manual review.
Related

More tools in the student workflow.

Score your essay before Turnitin does.

Free, no signup, 3 scans every day, 5,000 characters per scan. All three detection modes plus sentence-level highlights in every pass. Students with a .edu email get Pro at $13.99/mo.

Score my essay free See pricing
Pre-Turnitin draft scan. Sentence evidence on every flag. Free forever for normal essay volume.