Plagiarism Detector
FreeDetect plagiarism in any text with web source matching and originality analysis
Free, no signup required · Ctrl+Enter to submit
Plagiarism results appear here
Paste at least 30 words and click Check Plagiarism to scan for copied content
Checking for plagiarism...
Scanning web sources and analyzing text
How It Works
- 1
Paste Your Text
Copy and paste the text you want to check -- essays, reports, blog posts, or any written content. Minimum 30 words required; 50+ words recommended for the most accurate results.
- 2
Scan for Matches
The tool extracts key phrases from your text and searches the web for matches. It also analyzes sentence structure, cliche density, and vocabulary patterns to estimate originality.
- 3
Review Results
Get an overall originality score, matched source URLs with similarity percentages, and per-sentence analysis highlighting flagged passages. Use the Humanize feature to rewrite flagged text automatically.
Plagiarism detection has evolved beyond simple string matching. Modern plagiarism detectors need to catch not just verbatim copying but also close paraphrasing, patchwork plagiarism (cobbling together phrases from multiple sources), and template-based content that mimics original writing. The challenge is balancing sensitivity -- catching genuine plagiarism without flooding results with false positives from common phrases and widely-known information.
Coda One's Plagiarism Detector uses a multi-layered approach. First, it extracts distinctive phrases from your text and searches the web for exact and near matches. When matches are found, you see the source URL, the matching text, and a similarity percentage. Second, it analyzes text-level patterns: cliche density, vocabulary richness, sentence structure uniformity, and other signals that indicate content may have been assembled from templates or existing sources rather than written originally.
The combination of web matching and structural analysis provides more reliable detection than either method alone. A text with no exact web matches might still score lower on originality if its language is heavily generic and cliche-laden -- a common pattern in content that has been significantly paraphrased from sources. Conversely, a text with a few phrase matches but otherwise rich, varied language might score higher overall, indicating that the matches are likely coincidental rather than intentional copying.
Frequently Asked Questions
What types of plagiarism does this detect?
How does plagiarism detection differ from AI detection?
Can it detect plagiarism from paywalled sources?
What does the originality score mean?
Can I detect self-plagiarism?
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