See exactly which sentences look AI-generated and why. Get one-click tips to make your writing sound more human. Plus plagiarism and fact-checking.
Select text anywhere. Pick what you want to check.
Find out if text was written by ChatGPT, Claude, or other AI models.
Find if text was copied from existing sources on the web.
Verify if claims in the text are actually true.
More than just detection. We help you understand and fix.
See exactly which sentences are AI vs human. Color-coded for quick scanning.
Not just a score—plain English explanation of why text was flagged.
Specific suggestions to make AI text sound natural. Apply with one click.
Works inside Google Docs. Select text, check, and copy suggestions.
Works on GitHub, GitLab, Stack Overflow via Chrome extension.
Copy results or share links with teachers, editors, or clients.
Not to catch people — to help them sound more human
Check your essays before submitting. Fix flagged sentences.
Make AI-assisted content sound authentic before you post.
Deliver work that passes client AI checks. Verify your facts.
Polish AI-generated copy so it sounds like your brand voice.
Free for basic AI detection. Pro unlocks the full toolkit.
Basic AI detection for occasional use
10k words AI • 2k plagiarism • 2k fact-check
Everything you need to verify content
100k words AI • 15k words plagiarism • 25k words fact-check
Never pay again for Pro features
Unlimited AI • 250k plagiarism • 500k fact-check/year
GPTZero catches. We coach.
Other tools just flag your writing as AI. We show you exactly why each sentence was flagged and give you one-click tips to fix it. Same price as GPTZero, but we actually help you improve.
AI detection checks if text was written by an AI model like ChatGPT. Plagiarism check finds if text was copied from existing websites. AI-generated content is usually original (not plagiarized), but you might want to check both.
Our free tier uses 3 ML models that vote together. Pro adds Copyscape's commercial AI detector for higher accuracy. No AI detector is perfect—treat results as informed estimates. Sentence-level highlighting helps you see exactly which parts triggered detection.
We extract factual claims from your text (statistics, dates, historical facts, scientific claims) and verify them against web sources using Gemini. Each claim gets a verdict: True, False, Partially True, or Unverified—with source links.
These features use paid APIs that cost real money per query. Copyscape charges 3¢+ per plagiarism check. Gemini fact-checking requires web search calls. We bundle these into Pro so you get predictable pricing instead of pay-per-check surprises.
Yes! On GitHub, GitLab, Stack Overflow, and other code sites, we automatically switch to code detection mode. It looks for patterns like generic variable names, excessive comments, and uniform formatting that suggest AI generation.
No. Text is analyzed in real-time and not stored. We don't use your submissions to train models or share with third parties. Plagiarism and fact-checking queries go through third-party APIs (Copyscape/Gemini) subject to their privacy policies.
Check your writing, see what's flagged, fix it with one click.