AI Content Detector for PDFs

or drop files here

Our detector measures signals linked to machine-generated text: uniform sentence lengths (low burstiness), limited vocabulary variety and overused AI phrases.
  • ✓Transparent signals — See exactly why a score is high or low.
  • ✓Fast & private browser-based ai content detector — no installation needed
  • ✓Zero server uploads, zero daily limits & zero watermarks

AI Content Detector Without Losing Quality or Privacy

Results are an estimate, not proof — use them as one input alongside human judgment.

Fast & Effective AI Content Detector

Our detector measures signals linked to machine-generated text: uniform sentence lengths (low burstiness), limited vocabulary variety and overused AI phrases.

PDF

Transparent signals

Transparent signals: See exactly why a score is high or low. No sign-up: Unlimited checks.

100% On-Device Privacy, Trusted Worldwide

Your documents are processed entirely inside your browser memory using WebAssembly and HTML5 Canvas. Files never leave your computer or phone.

How To AI Content Detector Online for Free

  1. 1Upload your PDF.
  2. 2Review the AI-likeness score and signals.
  3. 3Use the insights to guide your review.
  4. 4Download your processed file instantly with zero watermarks.
🔒 frtools.io/pdf/compress-pdf
PDF3 Pages
-82% Size
8.4 MB1.5 MB ✓
annual-report-2026.pdf
AI Content Detector
Medium Compression✓

Balanced size & high visual quality

High CompressionFREE

Smallest file size (up to -90%)

Compress PDF →

Everything You Need in a AI Content Detector Tool

Work Immediately—No Installation

Use AI Content Detector directly in your browser—no software installations, sign-ups, or learning curves.

Works on Any Device

Run smoothly in Chrome, Safari, Edge, or Firefox on desktop, laptop, tablet, and smartphone.

Transparent signals

See exactly why a score is high or low.

GDPR & Client-Side Privacy

Your documents are processed locally on your device—we never collect, upload, or store your files.

No sign-up

Unlimited checks.

100% Free & Zero Watermarks

Every option is unlocked for free with no daily task timers, no paywalls, and no watermarks.

AI Content Detector FAQs

Yes. AI Content Detector on Fr. Tools is 100% free with no daily limits, no sign-up, no watermarks and no "Pro" paywall. Every option you see is unlocked.

Tutorials & Tips for AI Content Detector

<100KB
HOW TO USE AI CONTENT DETECTOR

How to AI Content Detector Online for Free in Seconds

Step-by-step guide to getting the fastest, cleanest result with AI Content Detector directly in your browser without installing software.

1 MB MAX
BEST PRACTICES

Keep Maximum Quality When Using AI Content Detector

Learn how our local WebAssembly engine preserves fonts, layout, and clarity while processing your document.

PRIVACY & WORKFLOW

Why On-Device AI Content Detector Is Safer for Sensitive Files

Understand how browser-based PDF processing protects confidential contracts, resumes, and financial records.

Document Work Made Easy

Boost productivity with unlimited, 100% free access to all of Fr. Tools’ private browser-based PDF tools for taking the hassle out of document work. Do more, better, faster.

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