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PDF AI Detector

Detect AI-generated text in any PDF or Word document with page-by-page scoring, sentence-level highlights, and metadata fingerprinting. Read the full document, and flag the sentences most likely written by an AI model.

Drop your document here or click to browse

PDF, DOCX, DOC, TXT up to 32MB

Trusted By Brands

Detect AI-Generated PDF Text

PDF AI Detector identifies AI-generated text at the document, page, and sentence levels. CudekAI highlights suspicious passages and explains the signals behind its score.

82%

Score Documents Page By Page

PDF AI Detector displays an overall AI score and per-page detection percentages. It highlights score patterns to help reviewers locate suspected AI content.

12%
88%
64%
9%
71%
95%
18%
40%

Analyze Text Sentence By Sentence

PDF AI Detector scores individual sentences and highlights likely AI, mixed, and human-written text. It helps reviewers examine specific passages beyond the overall document score.

Check PDF Metadata Fingerprints

PDF AI Detector examines PDF metadata to identify software and potential AI-generation clues. CudekAI adds metadata findings to text-based results without treating them as proof of AI authorship.

PDF

XMP

Explore All Detection Features

Flag Text From Any Model

Detects AI-generated text from GPT, Claude, Gemini, Qwen, DeepSeek, Grok, and other AI models. Covers chatbot output, AI writing tools, and automated workflows without requiring model identification.

Read Full Document Metadata

Extracts author, dates, PDF version, document IDs, XMP history, and security details. Displays document properties alongside detection results for further review.

Support PDF And Word Files

Accepts PDF, DOCX, DOC, and TXT files for text analysis. Reads selectable PDF text directly without format conversion.

Extract Text From Any Layout

Extracts text from complex layouts containing tables and images while preserving reading order. Shows extracted text alongside detection results for verification.

Handle Large And Scanned Files

Uses OCR to extract text from scanned PDFs and image-only documents. Flags incomplete extraction and offers a paste-text option when needed.

Read Your Full Report

Combines AI scores, page maps, sentence highlights, software details, and metadata findings in one report.

See How CudekAI PDF AI Detection Works

Read The Writing Signals

PDF AI Detector analyzes perplexity, burstiness, text rhythm, sentence pacing, and word predictability to identify AI-writing patterns. It scores each page independently while accounting for common writing variations.

Match Software Fingerprints

PDF AI Detector matches PDF metadata and text fragments against known tools, including ReportLab, WeasyPrint, Puppeteer, FPDF, and jsPDF. It treats matched fingerprints as supporting clues alongside writing signals.

Score The AI Indicators

PDF AI Detector assigns 40 points to strong indicators, 20 to medium, and 10 to low, with a maximum score of 100. It displays the total score, confidence percentage, and risk level, using a 25-point threshold for a likely AI-generated flag.

Why CudekAI Is The Best PDF AI Detector

Support Teachers And Educators

PDF AI Detector helps teachers, lecturers, and academic integrity teams check student submissions for AI-generated text.

Help Editors And Managers

CudekAI helps editors and content managers screen drafts, freelancer deliverables, and knowledge base articles before publication.

Assist Hiring And Recruiting Teams

CudekAI PDF AI Detector assists hiring teams review written applications, take-home assessments, and submitted work samples.

Serve Grant And Proposal Reviewers

CudekAI helps grant and proposal reviewers identify potentially AI-generated sections in funding applications and research proposals.

Equip Developers And Enterprises

PDF AI Detector gives developers and enterprise teams an API-accessible tool for screening documents at scale.

Detect AI In Three Steps

01

Upload Your Document

Upload a PDF, Word file, or text document by drag and drop, file browser, or paste. PDF AI Detector checks the file format before analysis.

02

Run The AI Analysis

PDF AI Detector analyzes document text and metadata for AI-generation signals. CudekAI returns the detection results when processing finishes.

03

Review The Highlighted Results

Review the document score, page map, sentence highlights, and metadata in one view. PDF AI Detector lets you read, copy, or download the report.

Why Choose CudekAI PDF AI Detector

Get Results In Real Time

PDF AI Detector delivers detection results without a processing queue. CudekAI helps reviewers check documents efficiently.

Protect Your Uploaded Files

PDF AI Detector uses HTTPS and does not use uploaded files for model training. CudekAI documents its file-handling policy and report-retention practices.

Use On Every Platform

PDF AI Detector works in a mobile-responsive browser and supports desktop browser extensions. CudekAI lets reviewers check selected text without opening a separate tool.

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Reviews

 Reviews

“The page-by-page scores help me locate sections that need a closer look. I don’t have to rely on one overall percentage.”

T

Teacher

“I use the sentence highlights to review submitted drafts more efficiently. They help me focus on specific passages.”

C

Content Editor

“The metadata report adds useful context when I review PDFs from different sources. I can check document details alongside the text score.”

R

Researcher

“Uploading Word files and PDFs in one place makes our initial review simpler. The report brings the main findings together.”

A

Academic Reviewer

“The detection score is a useful starting point for reviewing freelancer submissions. I still read the flagged passages before making a decision.”

C

Content Manager

Support

Find Answers To FAQs

What is a PDF AI detector?

PDF AI detector is a tool by CudekAI that analyzes document text to identify patterns associated with AI-generated writing. It provides an overall score, page-level results, sentence highlights, and PDF metadata findings.

How does PDF AI detection work?

PDF AI Detector analyzes writing patterns such as perplexity, burstiness, text rhythm, and word predictability. It can also examine document metadata for software fingerprints that provide additional context.

Is the PDF AI detector free?

Yes. CudekAI's PDF AI Detector offers free checks without sign-up, with limits on the number of checks and the characters per submission. Paid plans provide higher limits and greater character coverage.

What file types are supported?

PDF AI Detector accepts PDFs, DOCX, DOC, and TXT files up to 32MB. CudekAI can also let you paste text directly for analysis.

Can it detect ChatGPT and Claude text?

Yes. PDF AI Detector checks text from ChatGPT, Claude, Gemini, Grok, DeepSeek, Qwen, and other AI models without requiring you to identify the source model.

Does it check Word documents?

Yes. The detector accepts DOCX and legacy DOC files alongside PDFs and plain text. It analyzes the document text without requiring you to convert it to PDF first.

How accurate is document-level detection?

PDF AI Detector provides overall and page-level scores to help reviewers locate potentially AI-generated passages. Its results are indicators, not definitive proof of authorship, and should be assessed alongside human review.

Can it detect AI in scanned PDFs?

Yes. OCR extracts text from scanned and image-only PDFs before analysis. Results depend on the scan quality and how accurately the text can be extracted.

Is my uploaded file kept private?

CudekAI states that uploaded files are transmitted over HTTPS and are not used to train its models. Check the current privacy policy for exact storage and deletion periods.

How many pages or words can I check for free?

The free plan checks the start of your document, up to a per-submission character limit, with a limited number of checks. CudekAI’s paid plans offer higher limits and greater character coverage.

Can it prove who wrote a document?

No. A detection score and metadata clues cannot establish who authored a document. PDF AI Detector can support a review but does not replace independent evidence.

Does it work on mobile?

Yes. PDF AI Detector works through a mobile-responsive browser. CudekAI’s Chrome extension is intended for compatible desktop browsers.

What is the difference between per-page and sentence scores?

Per-page scores show the distribution of suspected AI-generated text across a document. PDF AI Detector sentence scores highlight individual passages for closer review.

Can PDF metadata prove AI authorship?

No. Creator, Producer, and XMP fields can suggest which software generated a PDF, but they do not prove who wrote its contents. CudekAI metadata should be considered alongside text-based results.

Detect AI in your first document free