Quillbot Review 2025: Is Quillbot The Best AI Checker Tool?

You're reading a student essay. The writing is polished, the arguments are clear, but something feels off. Is this their work, or did ChatGPT write it?

This question has become routine for educators, content managers, and anyone who needs to verify authenticity. The problem? Most AI Checker tools either cost too much, lack accuracy, or require subscriptions for basic features.

QuillBot's AI Checker is one of the most talked-about solutions. It's part of a popular writing suite, promises accurate detection, and offers detailed analysis. But here's the thing: is it worth the premium price tag, or are there better free AI Checker alternatives?

In this review, we'll test QuillBot's AI Checker capabilities, compare it with Dechecker—a specialized free AI Checker that's gaining traction—and help you decide which tool actually delivers on its promises.

What Is an AI Checker Tool?

An AI Checker (also called an AI Detector or AI content detector) uses artificial intelligence to analyze text and determine the likelihood that it was generated by AI tools like ChatGPT, Claude, Gemini, or other language models.

What sets best AI Checker tools apart?

Unlike simple pattern matching, advanced AI Checker tools analyze writing patterns, sentence structure, perplexity (predictability), and burstiness (sentence length variation) to identify machine-generated text. The best tools can distinguish between content that's fully AI-generated, human-written but AI-refined, and completely human-written.

Why AI Checker Tools Matter: Solving the AI-Generated Content Problem

While "What Is an AI Checker Tool?" explains how these tools work, understanding why they matter reveals the real-world challenges they solve.

The Growing Problem

AI-generated content is flooding every corner of the internet. Students submit essays written entirely by ChatGPT. Job applicants send AI-crafted cover letters. Content creators publish AI-generated blog posts. The problem? It's becoming impossible to distinguish authentic work from machine-generated text.

This creates real consequences:

• Academic integrity: Students bypass learning by submitting AI work
• Professional credibility: Employers can't assess genuine skills
• Content quality: Readers lose trust when content feels generic
• SEO penalties: Search engines may penalize overly AI-generated content

How AI Checker Tools Solve This

AI Checker tools don't just identify problems—they enable solutions:

1. Maintain Authenticity

When you can detect AI-generated content, you can ensure that submissions, applications, and publications represent genuine human work. This protects academic standards, hiring processes, and content quality.

2. Enable Fair Assessment

Without AI Checker tools, educators and employers can't fairly evaluate work. Some students or candidates might use AI while others don't, creating an uneven playing field. Detection tools level that field.

3. Preserve Trust

Readers, clients, and stakeholders need to trust that content is authentic. AI Checker tools help maintain that trust by identifying when content might be machine-generated.

4. Support Ethical AI Use

Not all AI use is problematic. AI Checker tools help distinguish between ethical AI assistance (like grammar checking) and problematic AI generation (like submitting fully AI-written work). This nuance matters.

The Difference from "What Is"

• "What Is" explains the technical mechanism—how AI Checker tools analyze text patterns and identify AI-generated content.
• "Why It Matters" explains the real-world impact—why detecting AI-generated content solves actual problems in education, hiring, content creation, and trust.

Understanding both is crucial: the "what" helps you choose the right tool, while the "why" helps you understand when and why to use it.

QuillBot AI Detector: Key Features

QuillBot's AI Checker is part of the larger QuillBot writing suite, which includes paraphrasing, grammar checking, and other writing tools. Here's what it offers:

✔️ Detection Capabilities

• Supports detection of ChatGPT, GPT-4, GPT-5, Gemini, Claude, Llama, and other AI models
• Identifies AI-generated content, AI-refined content, and human-written content
• Provides percentage scores for each category
• Sentence-level analysis showing which parts appear AI-generated

✔️ User Experience

• Clean, intuitive interface
• Fast detection (results in seconds)
• Multilingual support (all languages)
• Downloadable PDF reports
• No sign-up required for basic use

✔️ Technical Features

• Advanced AI models for high accuracy
• Detailed analysis with highlighted sections
• Pattern recognition based on perplexity and burstiness metrics

Why QuillBot's AI Checker Stands Out

QuillBot's AI Checker has several advantages that make it popular:

1. Comprehensive Detection

Unlike some AI Checker tools that only flag fully AI-generated content, QuillBot distinguishes between three categories:

• AI-generated: Content created entirely by AI
• Human-written & AI-refined: Content written by humans but improved with AI tools
• Human-written: Content created without AI assistance

This nuanced approach helps users understand not just whether AI was used, but how it was used.

2. Detailed Analysis

QuillBot's AI Checker provides sentence-level analysis, showing exactly which parts of the text appear to be AI-generated. This granular feedback is valuable for educators and content managers who need to understand the extent of AI usage.

3. Integration with Writing Tools

Since QuillBot's AI Checker is part of a larger writing suite, users can check content and then use other QuillBot tools (like the Paraphraser or Grammar Checker) to improve it—creating a complete workflow.

4. Trusted by Institutions

QuillBot is used by writers at top institutions, which adds credibility to its AI Checker tool. The company emphasizes that its detector can identify content refined with paraphrasers or grammar checkers, including QuillBot's own tools.

How to Use QuillBot's AI Checker

QuillBot's AI Checker follows a straightforward three-step process:

Step 1: Add Content

Input text: Upload or paste your text into the AI Checker input field. The tool accepts text from various sources—documents, emails, blog posts, or any written content you want to check.

Select language: Choose your text's language from the dropdown menu. QuillBot supports English, French, German, Spanish, and all other languages for accurate detection.

Check length: Make sure your text meets the minimum requirement of at least 80 words. Longer texts generally provide more accurate detection results, as the AI Checker analyzes patterns across the entire document.

Step 2: Run Scan

Analyze text: Click the "Detect AI" button at the bottom of the tool. QuillBot's AI Detector will analyze your text using advanced algorithms that examine writing patterns, sentence structure, and other indicators.

Receive report: Get detailed results in just a few seconds. The report shows three percentage scores:

• AI-generated: Content created entirely by AI
• Human-written & AI-refined: Content written by humans but improved with AI tools
• Human-written: Content created without AI assistance

Review feedback: Receive both a total score and a line-by-line report. The sentence-level analysis highlights exactly which parts of your text appear to be AI-generated, making it easy to identify specific sections that need attention.

Step 3: Edit Content (Optional)

Interpret results: Review any highlighted sections of text. Remember that QuillBot's AI Detector provides probability scores—not guarantees. Use your judgment when interpreting results, especially for content that might have legitimate reasons for appearing AI-generated (like technical writing or non-native speaker content).

Revise text: If you identify AI-generated sections that need to be more human-like, rewrite them manually or use QuillBot's other tools (like the Paraphraser or AI Humanizer) to improve them.

Re-scan: Run another scan to double-check your revisions. This helps ensure that your edits successfully made the content more authentic.

Limitations of QuillBot's AI Detector

While QuillBot's AI Detector is powerful, it has some limitations:

❌ Premium Features Required

Many advanced features, including detailed reports and higher word limits, require a QuillBot Premium subscription (around $19.95/month). The free version has limitations that may not meet all users' needs.

❌ Accuracy Concerns

Like all AI Checker tools, QuillBot's detector isn't 100% accurate. False positives and false negatives can occur, especially with:

• Content written by non-native speakers
• Highly technical or formulaic writing
• Content that's been heavily edited after AI generation

❌ Limited Free Features

The free version has restrictions on word count and report features, which may be limiting for users who need to check longer documents regularly.

The Best Alternative to QuillBot's AI Detector

While QuillBot's AI Detector is a solid tool, its premium requirements and lack of integrated humanization create gaps for many users. Based on comprehensive testing and user feedback, Dechecker emerges as an excellent alternative that addresses these limitations.

Dechecker is a specialized free AI Checker designed specifically for AI content detection. Unlike QuillBot's detector, which is part of a larger writing suite, Dechecker focuses entirely on providing accurate, accessible AI Detector functionality.

Why Dechecker Stands Out

1. Completely Free

Dechecker offers full AI Checker functionality without subscription requirements. Users can check up to 20,000 characters per submission, making it suitable for longer documents and regular use.

2. Integrated Humanization

When Dechecker's AI Detector identifies AI-generated content, users can immediately humanize it within the same platform. This integrated workflow saves time and eliminates the need for multiple tools.

3. Sentence-Level Analysis

Like QuillBot, Dechecker provides detailed sentence-level analysis, showing which parts of the text are likely AI-generated. This granular feedback helps users understand the extent of AI usage.

4. High Accuracy

Dechecker uses advanced AI models to detect content from ChatGPT, Claude, Gemini, and other major AI platforms. Its accuracy is comparable to QuillBot's detector while remaining completely free.

5. User-Friendly Interface

Dechecker's interface is clean, intuitive, and focused specifically on AI content detection. Users don't need to navigate through multiple tools to find what they need.

How to Use Dechecker

1. Visit Dechecker.ai
2. Paste your text (up to 20,000 characters)
3. Click "Detect AI"
4. Review results with sentence-level analysis

QuillBot vs. Dechecker: A Detailed Comparison

When choosing an AI Checker tool, it's important to compare options. Here's how QuillBot's AI Detector stacks up against Dechecker, a popular free AI Checker alternative:

Key Differences

1. Pricing Model

QuillBot's AI Detector offers a free tier with limitations, but many advanced features require a Premium subscription. Dechecker provides full AI Checker functionality for free, making it more accessible for users who need regular detection without subscription costs.

2. Humanization Integration

One significant advantage of Dechecker is its integrated humanization feature. When the AI Checker identifies AI-generated content, users can immediately humanize it within the same platform. QuillBot requires users to use separate tools for this functionality.

3. Free Tier Limitations

QuillBot's free AI Detector has word count and feature restrictions that may limit its usefulness for regular users. Dechecker offers more generous free limits (20,000 characters per check), making it suitable for longer documents and frequent use.

4. Detection Accuracy

Both tools use advanced AI models and provide high accuracy. However, Dechecker focuses specifically on AI content detection, while QuillBot's detector is part of a broader writing suite, which may affect its specialization.

Final Thoughts: Is QuillBot the Best AI Checker Tool?

QuillBot's AI Detector is a powerful tool with strong detection capabilities and detailed analysis features. For users already invested in QuillBot's ecosystem, it's a valuable addition.

However, for users seeking a specialized free AI Checker with integrated humanization and no subscription requirements, Dechecker offers a compelling alternative. Its focus on AI content detection, generous free limits, and integrated humanization make it ideal for educators, content managers, and anyone who needs reliable AI Checker functionality without premium costs.

The best AI Checker tool depends on your specific needs:

• Choose QuillBot if you're already using QuillBot Premium and want integrated writing tools
• Choose Dechecker if you need a specialized free AI Checker with humanization capabilities

Both tools provide accurate AI content detection, but Dechecker offers better value for users who prioritize free access and integrated workflows.

👉 Try Dechecker today — the free AI Checker that detects and humanizes AI content in one platform. No sign-up. No fees. Just accurate detection and powerful humanization.