AI content is everywhere - and so are the tools to detect it. Whether you’re an educator checking student work, a publisher verifying freelancer submissions, or a content creator who wants to ensure your AI-assisted writing passes muster, you need the right tools.

This guide covers both sides: detectors that catch AI content, and humanizers that help you rewrite AI text to sound more natural. We tested the leading tools to help you choose based on your specific needs.

A note on ethics: Humanizers have legitimate uses (improving AI drafts, avoiding false positives) but shouldn’t be used to misrepresent AI work as human-written in contexts where that matters, like academic submissions.

What We Looked For

When evaluating these tools specifically for this use case, we focused on:

  • Detection accuracy across multiple AI models (ChatGPT, Claude, Gemini)
  • False positive rate on human-written content
  • Humanization quality and readability of output
  • Speed and ease of use
  • Price relative to volume needs
  • Integration options (browser extensions, LMS, API)

Quick Comparison

ToolBest ForStarting PriceFree TierOur Rating
Originality.aiPublishers, content agencies, and SEO teams who…$12/monthly❌ NoN/A
GPTZeroEducators, students, and anyone who needs relia…$15/monthly✅ YesN/A
CopyleaksInternational teams and developers needing mult…$13/monthly✅ YesN/A
Walter Writes AIStudents and content creators who need quick hu…$10/monthly✅ YesN/A
Undetectable AISEO professionals and bloggers who need reliabl…$10/monthly✅ YesN/A
BypassGPTUsers who want mode flexibility and specific de…$12/monthly✅ YesN/A

Detailed Reviews

Originality.ai

The most accurate AI and plagiarism detector for publishers

Pricing: $12/monthly | No free tier $12.95/mo if billed annually. Pay-as-you-go option at $30 for 3,000 credits.

What we like:

  • ✅ Industry-leading accuracy (99%+ claimed) across ChatGPT, GPT-4, Claude, Gemini
  • ✅ Combined AI detection + plagiarism checking in one scan
  • ✅ Chrome extension for Google Docs integration
  • ✅ Full site scanning capability for publishers
  • ✅ Fact-checking feature to catch AI hallucinations

What to watch out for:

  • ⚠️ No free tier (only pay-as-you-go or subscription)
  • ⚠️ Credits expire monthly on subscription plans
  • ⚠️ Can be expensive for high-volume scanning

Best for: Publishers, content agencies, and SEO teams who need the most accurate detection

Try Originality.ai →


GPTZero

The world’s

Pricing: $15/monthly | Free tier: 10,000 words/month, 7 scans per hour Essential $15/mo, Premium $24/mo (includes plagiarism). 33% off annual plans.

What we like:

  • ✅ Generous free tier for occasional checking
  • ✅ Purpose-built for education with LMS integrations (Canvas, Moodle)
  • ✅ Sentence-level highlighting shows exactly which parts are AI
  • ✅ Chrome extension for quick checks
  • ✅ Writing report feature shows the writing process

What to watch out for:

  • ⚠️ Plagiarism checking only on Premium plan
  • ⚠️ Free tier limited to basic scans
  • ⚠️ Some false positives reported on heavily edited content

Best for: Educators, students, and anyone who needs reliable free AI detection

Try GPTZero →


Copyleaks

AI-powered plagiarism and AI content detection trusted by millions

Pricing: $13/monthly | Free tier: 20 pages/month AI Only $9.99/mo, AI+Plagiarism $16.99/mo. 100 credits per plan.

What we like:

  • ✅ Detects AI in 30+ languages
  • ✅ Unique source code plagiarism detection (Java, Python, etc.)
  • ✅ Enterprise-grade security (SOC2, GDPR compliant)
  • ✅ LMS integrations (Canvas, Blackboard, Moodle)
  • ✅ Cross-language plagiarism detection

What to watch out for:

  • ⚠️ Separate plans for AI-only vs AI+Plagiarism
  • ⚠️ Credit system can be confusing
  • ⚠️ Some reports of false positives on older content

Best for: International teams and developers needing multi-language and code detection

Try Copyleaks →


Walter Writes AI

AI humanizer that bypasses Turnitin, GPTZero, and Originality

Pricing: $10/monthly | Free tier: 300 words trial Starter $10/mo (10k words), Pro $17/mo (55k words), Unlimited $56/mo. 30% off annual.

What we like:

  • ✅ Fastest-growing humanizer (+1000% Google Trends growth)
  • ✅ Built-in AI detector to verify results
  • ✅ Multiple humanization modes for different use cases
  • ✅ Claims to bypass Turnitin and major detectors
  • ✅ Supports 80+ languages

What to watch out for:

  • ⚠️ Mixed reviews on output quality (some grammatical issues reported)
  • ⚠️ Strict refund policy (3 days, 1,500 words max)
  • ⚠️ Newer tool with less track record

Best for: Students and content creators who need quick humanization with verification

Try Walter Writes AI →


Undetectable AI

Make your AI-generated content truly undetectable

Pricing: $10/monthly | Free tier: Limited free checks Monthly $9.99, Yearly $59. Custom business plans available.

What we like:

  • ✅ Established player with proven track record
  • ✅ Clean, simple interface
  • ✅ Multiple humanization levels
  • ✅ Good for SEO content that needs to avoid AI penalties
  • ✅ Embeddable widget for websites

What to watch out for:

  • ⚠️ Results vary depending on input quality
  • ⚠️ Some plans have word limits per request
  • ⚠️ May require multiple passes for best results

Best for: SEO professionals and bloggers who need reliable humanization at scale

Try Undetectable AI →


BypassGPT

AI detector bypasser with multiple humanization modes

Pricing: $12/monthly | Free tier: 80 words per input on free tier Basic $12/mo (5k words), Pro $19/mo (30k words), Unlimited $49/mo.

What we like:

  • ✅ Three modes (Fast, Creative, Enhanced) for different needs
  • ✅ Claims to remove ChatGPT watermarks
  • ✅ Built-in AI checker to verify results
  • ✅ Bypass Turnitin and Originality.ai specifically targeted

What to watch out for:

  • ⚠️ Credits expire monthly (don’t roll over)
  • ⚠️ Some users report meaning changes in output
  • ⚠️ Refund policy is strict (30 minutes, 1000 words)

Best for: Users who want mode flexibility and specific detector targeting

Try BypassGPT →


Frequently Asked Questions

What’s the most accurate AI detector?

Originality.ai consistently ranks highest in third-party accuracy tests, with 99%+ detection rates across major AI models. GPTZero and Copyleaks are close behind. However, no detector is perfect - they all have some false positive rate on human content.

Can AI humanizers really bypass all detectors?

No tool guarantees 100% bypass rates. Most humanizers work by restructuring sentences and varying word choice to reduce AI patterns. Results depend heavily on the input quality and how much editing you’re willing to do afterward. Always verify with multiple detectors.

Is using an AI humanizer cheating?

It depends on context. Using humanizers to polish AI-assisted content for blogs or marketing is generally fine. Using them to submit AI work as your own in academic settings violates most integrity policies. Know your institution’s rules.

Why does my human-written content get flagged as AI?

Detectors look for statistical patterns, not actual authorship. Highly formulaic writing, certain phrasings, or technical content can trigger false positives. If you’re consistently flagged, try varying your sentence structure and adding more personal voice.

Should I use a detector or humanizer?

Detectors if you’re checking others’ work (educators, editors, publishers). Humanizers if you’re creating content and want to ensure it reads naturally. Many users need both - detect to check, humanize to fix flagged sections.

What’s the best free option?

For detection, GPTZero’s free tier (10,000 words/month) is the most generous. For humanization, Walter Writes offers a 300-word free trial. Undetectable.ai also has limited free checks. Test before committing to paid plans.

The Bottom Line

For most people looking at this use case, Originality.ai offers the best balance of features and value. However, your specific needs matter:

  • On a budget? Start with the free tiers from Copy.ai or ChatGPT
  • Running a sales team? Lavender or Instantly give you the specialized features you need
  • Need maximum personalization? SmartWriter’s prospect research is unmatched

The best tool is the one you’ll actually use consistently. Most offer free trials, so test 2-3 before committing.


Last updated: December 2025. Prices and features verified as of this date.