Free AI checkerby DetectGPT
Advanced AI Content Detector for ChatGPT, GPT-5 & Other LLMs
Looking for an AI detector? Our free AI checker tool lets you analyze your writing without an account or login. Simply paste your draft or enter a page URL to check whether your text is AI-generated or not.
- 5,000
- Words
- Free
- No signup
- Any LLM
- ChatGPT and more
No signup. Checks stay on this device.
Why Choose DetectGPT for AI Detection
DetectGPT reads the words you paste without a login, a campus license, or the original prompt. Drop in text from any model, or text you wrote yourself, and see how machine it sounds.
5,000 words per run
Paste a full essay-length draft. Split anything longer and run it in chunks.
Paste text or a homepage URL
Drop the words in the box, or analyze a public page without logging into the site.
Works on any LLM draft
ChatGPT, Claude, Grok, Gemini, or something you wrote yourself. DetectGPT is the brand, not one model.
Report you can actually read
A percentage plus yellow, orange, and red passages, so you can see which lines still sound like a model.
Rephrase the red lines
Hover a red sentence to see why it scored that way, then rephrase that line. The draft is scored again, so the percentage can move.
No account, no campus login
Run it in a browser. Nobody at school has to share Feedback Studio with you.
Share a result link
Send the report without making someone paste the draft again.
Quick reference
At a glance
- Best for
- Anyone who used a model and wants a look before someone else does
- Checks
- The finished draft, or a public URL. Not your ChatGPT, Claude, or Grok account
- Time
- Under a minute for 5,000 words
- Cost
- Free, no account
- Unlimited words
- Unlimited checks, no daily cap. 5,000 words per run
- Word cap
- 5,000 words per run. Split longer pieces
- URL scan
- Homepages, articles, public posts. Not login walls or PDFs
- Output
- A percentage plus highlighted lines
- Languages
- Strongest on English
- Proof of authorship?
- No. Style, not a courtroom
- Similarity check
- Plagiarism Checker tab. Public web overlap, 3,000 words
- Similarity score
- A percentage plus matching phrases and source links
The tell
What DetectGPT actually looks at
Language models pick the next likely word, which leaves a fingerprint of even sentence length, generic transitions, and adjectives that never take a side. DetectGPT scores those habits on the finished draft only. It does not open your ChatGPT, Claude, or Grok account and never sees the prompt.
A tidy student essay and a lightly edited Claude memo can both trip it, because the question is not who typed this. It is whether the draft still sounds like a model.
The number
How to read the AI percentage
The number is a share of the prose that looks machine-made rather than a probability that you cheated. Forty percent means a chunk of the draft still sounds like a model, not a 40% chance of a misconduct case.
How to read results. The percentage is the share of analyzed words in sentences flagged as AI-like. The colors mark those same sentences. Style signal only, not proof of authorship. Details: how it works.
Under ~20%
Weak signal. Lots of human writing lives here. Do not treat it as a pass.
20% to 50%
Mixed. Some lines drone. Read it out loud and rewrite the stiff bits.
Over 50%
The draft still sounds like a model. Keep your facts. Change the voice.
Walkthrough
How to use DetectGPT
- 1
Paste at least 50 words, or drop in a public URL including a homepage.
- 2
Stay under 5,000 words, or split a longer piece.
- 3
Hit Check AI score and wait for the report.
- 4
Read the percentage, then the lines that lit up.
- 5
Rewrite the stiff parts in your own voice and keep a copy of each version.
Also on DetectGPT
Similarity score check
DetectGPT also has a plagiarism checker. Open the Plagiarism Checker tab, paste up to 3,000 words, and it will look for matching phrases on public pages, then list the source next to each hit so you can see what overlapped instead of staring at a crayon.
If you needed a free plagiarism checker for students, use the Plagiarism Checker tab or open the free plagiarism checker: paste the draft, run the similarity score, and read the source list.
The similarity score is web overlap rather than an AI writing percentage or a campus originality report, so quoted facts and common textbook lines can light up without anyone copying an essay. Use it as a first look and read the sources before you treat the number as a verdict.
Audience
Who is DetectGPT for
Students
A private pass over a paper before you hand it in, especially if you used a model for an outline or a first pass.
Teachers and writers
Catch the glue phrases that make a post sound generated before a client or editor does. The check on this page is the same one, written for a stack of essays.
People writing in a second language
Careful, even prose is a known false alarm, so use the score to vary rhythm instead of panicking.
Side by side
DetectGPT vs other checkers
DetectGPT, ZeroGPT, and campus tools such as Turnitin® all look for AI-writing style signals, but they are separate products. None of them reprints another tool’s number, and DetectGPT does not use the Turnitin engine, match campus scores, or predict a Turnitin result.
DetectGPT is the free self-check on this page: paste a draft or public URL, get an AI writing percentage plus highlighted lines, no school login. Campus reports (including Turnitin® AI indicators) usually appear only after submission inside an LMS. For a deeper Turnitin-focused walkthrough, see the free Turnitin AI checker page.
| DetectGPT | Other Checkers | |
|---|---|---|
| Who can use it | Anyone in a browser | A public site, a paid plan, or a school license |
| Cost | Free | A free tier, paid extras, or an institutional license |
| School login | No | Sometimes, through the course site |
| Self-check before submit | Yes | Sometimes. Campus reports are usually for instructors |
| AI writing score | Yes, on this page | Often a percentage or an AI indicator. Not this page’s number |
| Word cap | 5,000 per run | Varies by plan, or the file you submit |
| Plagiarism index | No | Some are style only. Campus tools often include one |
| Public similarity check | Yes, web overlap | Not always. Campus tools use their own report |
| What it reads | Finished prose from any LLM | Finished prose, or a file submitted for the course |
| Official campus tool | No | Only if the school licenses one |
| Affiliation | Independent | Separate products. Not DetectGPT |
Turnitin® is a registered trademark of Turnitin, LLC. DetectGPT is not affiliated with Turnitin® or ZeroGPT.
Limits
What DetectGPT cannot do
It cannot prove who wrote a sentence.
It cannot match a school’s private report one for one.
It cannot scan images, slides, or scanned PDFs. Paste the prose.
It cannot bless a draft against a syllabus. Policy still sits with you.
It cannot hit 0% on honest writing every time. Humans are not random either.
Nov 4, 2026
What's New
Sentence-Level Rephrasing
Rephrase individual sentences directly within your analyzed text without rewriting the entire document.
Real-Time Score Updates
AI detection scores now update instantly as sentences are rephrased, allowing you to see how each change affects your results.
Redesigned Interface
A completely refreshed design with improved navigation, cleaner layouts, and a more intuitive user experience.
Clearer sentence highlights
Reports still show a percentage plus yellow, orange, and red passages so you can see which lines still sound like a model — then rephrase a line and watch the score update.
Improved Performance
Faster analysis, smoother interactions, and a more responsive detection experience.
FAQs
- Is DetectGPT free?
- Yes. No account, no card, 5,000 words per run. Paste text or analyze a public URL.
- Does DetectGPT only check ChatGPT?
- No. DetectGPT is the brand. It scores writing from ChatGPT, Claude, Grok, Gemini, and other models. It never logs into those labs.
- Can I analyze a URL or a homepage?
- Yes. Use Analyze URL, paste a public page, including a homepage. We pull the readable text and score it. Login walls, PDFs, and apps will not work.
- Does DetectGPT have a plagiarism checker?
- Yes. Open the Plagiarism Checker tab, paste up to 3,000 words, and run a similarity score check. It looks for matching phrases on public web pages and lists source links. It is not a student paper archive and it will not reprint a campus similarity report.
- What is the similarity score on DetectGPT?
- It is the overlap percentage from the plagiarism checker: how much of the pasted draft matched public pages, plus the phrases and links. Cited facts and common textbook lines can score high. Open the sources before you treat the number as a verdict.
- Will DetectGPT match another AI score?
- No. Checkers do not share one percentage. Use DetectGPT as a comparable style check, then edit. Do not screenshot one dashboard as proof against another.
- Do you keep the draft I paste?
- Text you paste is scored in your browser. History stays on this device. If you analyze a URL, our servers fetch that public page so we can read it. Do not paste secrets.
- What percent AI is acceptable?
- There is no official cutoff. Scores under about 20% are noisy on most checkers. Your course or client policy is the real rule. Do not chase 0%.
- How accurate is AI detection?
- It is a usable signal and a weak judge. Short text, formulaic academic prose, and second-language writing produce more false alarms. Detectors also disagree with each other.
- What is the best AI detection tool to run before I submit?
- The one you can actually open. DetectGPT is the free checker on this page. Other public dashboards exist, and campus reports usually are not open to students. No tool reprints another tool’s number. Rewrite the stiff lines either way.
- Is DetectGPT the same as ZeroGPT?
- No. ZeroGPT is a different company’s public AI detector. DetectGPT is this site: paste a draft or a page URL, get an AI writing score, and open the plagiarism checker on the other tab. The two tools will not print the same percentage.
- How does DetectGPT compare to ZeroGPT?
- Both can be opened in a browser without a school login. DetectGPT scores up to 5,000 words, highlights the stiff lines, and can analyze a public page. ZeroGPT is a separate dashboard with its own limits. Use either result as a second look at the writing, not as proof of who typed it.
- How does DetectGPT relate to Turnitin®?
- DetectGPT is an independent self-check you can run in a browser. Turnitin® is a campus product most students only see after they submit. Same kind of AI-writing style signal, not the same software — DetectGPT does not reproduce or predict Turnitin scores. For Turnitin-specific detail, use the free Turnitin AI checker page.
Paste the draft
Paste up to 5,000 words as text or a homepage URL.
Read the score
A percentage for how machine the draft sounds.
Fix the voice
Rewrite the stiff lines and keep a copy.
The bottom line
Write the way you write, run the checker, and fix the lines that still sound generated. If a passage is still stiff, the AI humanizer can loosen it. Keep a copy of each version.
DetectGPT will not make you a better writer, but it will show you where the draft still talks like a model, and that is the part worth fixing. The how it works page walks through the score, and the blog covers the campus questions people ask next.
Try DetectGPT free today