AI Checker: Detect AI-Generated Text Sentence by Sentence
Our AI checker analyzes every sentence of your document individually and identifies content generated by ChatGPT, Gemini, Claude, Llama, and other large language models. Results delivered by email in 15 minutes from just $0.29/page.
How Our AI Checker Works
AI-generated text has statistical fingerprints that differ from human writing. Our checker identifies those patterns sentence by sentence.
Upload Your Document
Upload your paper as PDF, DOCX, DOC, or TXT. We extract the text and analyze the full content, handling documents from short essays to full dissertations.
Sentence-by-Sentence Analysis
Every sentence is scored individually using statistical language models. The AI checker looks for entropy patterns, vocabulary choices, and syntactic structures that distinguish AI from human writing.
Receive AI Detection Report
Your report arrives by email within 15 minutes. Each sentence is color-coded and scored on the 25–75 scale, with an overall AI probability for the entire document.
Which AI Models Does the Checker Detect?
Our AI checker is trained on outputs from all major large language models and is continuously updated as new models are released.
ChatGPT
GPT-3.5, GPT-4, GPT-4o, and all OpenAI API-based outputs are detected with high accuracy.
Google Gemini
Gemini 1.0 and 1.5 (Pro, Ultra, Flash) outputs are included in the detection model's training data.
Claude (Anthropic)
Claude 2, Claude 3 (Haiku, Sonnet, Opus) and newer Claude models are reliably detected.
Llama (Meta)
Meta's Llama 2 and Llama 3 models, often used via open-source tools and local deployments.
Mistral
Mistral 7B, Mixtral, and related open-weight models used in many AI writing tools.
Copilot & Bing AI
Microsoft Copilot and other GPT-4-based systems are covered through ChatGPT detection.
AI Writing Tools
Jasper, Writesonic, Copy.ai, Quillbot AI writer, and similar tools that call underlying LLMs.
Future Models
Our detection model is continuously updated as new LLMs are released to maintain detection accuracy.
The AI Detection Scale: 25 to 75
Unlike tools that give a binary "AI" or "Human" verdict, our AI checker provides a nuanced probability score for each sentence. This granularity helps you understand mixed documents more accurately.
High confidence that this sentence was written by a human. Natural variation, personal voice, and imperfect sentence structure are typical indicators.
The sentence shows mixed characteristics. Could be human text with an unusually formal style, edited AI text, or AI-assisted writing where a human made changes.
High confidence that this sentence was generated by an AI. Characteristics include overly smooth transitions, predictable vocabulary, and high token-level predictability.
Sample AI Detection Report
Example scores in brackets: [28] = human, [52] = uncertain, [71] = AI
What's Included in Your AI Checker Report
Sentence-Level Scores
Every sentence in your document receives an individual AI probability score on the 25–75 scale, giving you precise insight into which parts of the text are problematic.
Color-Coded PDF Report
AI-generated sentences are highlighted in the report — green for human text, yellow for uncertain, red for AI-generated — making it easy to identify problem areas instantly.
Results in 15 Minutes
Your AI detection report is generated and emailed to you within 15 minutes of upload and payment. Fast enough to review and revise before an academic deadline.
All Major LLMs Covered
ChatGPT, Gemini, Claude, Llama, Mistral, and more. Our detection model is trained on text from all major AI systems and is regularly updated.
Document-Level Summary
In addition to per-sentence scores, you receive an overall document-level AI probability score — giving your supervisor or professor a clear, concise summary statistic.
GDPR-Compliant Processing
Your document is analyzed securely within Europe and never stored in an external database. Full compliance with European data protection regulations.
AI Checker Pricing
Choose the AI Scan alone, or save 33% with the Combo package that includes full plagiarism checking too.
AI Scan
AI detection sentence by sentence
- Checks every sentence
- Scale: 25 (human) to 75 (AI)
- Results in 15 minutes
- All major LLMs detected
Combo: Plagiarism + AI
Best value — both scans together
- Full plagiarism check (70B+ sources)
- AI detection per sentence
- Two reports, one price
- Recommended for theses
Plagiarism Scan
Plagiarism check without AI detection
- 70B+ sources
- Color-coded PDF report
- Source links included
- Results in 15 minutes
AI Checker — Frequently Asked Questions
Our AI checker detects text generated by all major large language models, including ChatGPT (GPT-3.5, GPT-4, GPT-4o), Google Gemini, Anthropic Claude, Meta Llama, Mistral, and AI writing tools built on top of these models (Jasper, Writesonic, Copy.ai, etc.). The detection works at the sentence level, so even documents that are only partially AI-written are identified accurately.
Each sentence receives a score from 25 to 75. A score of 25 means high confidence that the text is human-written. A score of 75 means high confidence that the text was AI-generated. Scores in the middle range (35–60) indicate uncertainty — perhaps edited AI text, AI-assisted writing, or unusually formal human writing. Each sentence is scored individually for granular insight.
Our AI checker achieves high detection accuracy for text produced by current large language models. Sentence-level analysis reduces false positives compared to document-level tools. However, AI detectors operate on statistical patterns — heavily edited AI text or highly formal human writing may occasionally appear in uncertain territory. For best results, combine with our plagiarism check using the Combo package.
Yes. ChatGPT (all versions including GPT-4o) is one of the primary targets of our AI detection model. The checker recognizes the characteristic patterns of ChatGPT output — including predictable sentence structures, formulaic transitions, and specific vocabulary tendencies — with high accuracy.
You can upload PDF, DOCX, DOC, or TXT files up to 50 MB. The system extracts the text from your document automatically and runs the full AI analysis on the extracted content. Scanned PDFs (image-only, without selectable text) cannot be processed — please export a text-based version from your word processor.
If your university requires both a plagiarism check and AI detection — as many now do — the Combo package at $0.39/page gives you both for 33% less than booking separately. For a thesis or dissertation, Combo is strongly recommended. If you only need AI detection (e.g., you've already completed a plagiarism check elsewhere), the standalone AI Scan at $0.29/page is the right choice.
Check Your Paper for AI-Generated Text
Upload your document and receive a sentence-by-sentence AI detection report in 15 minutes. Starting at just $0.29/page — no registration required.
100% money-back guarantee · Results in 15 min · GDPR compliant