Professional code plagiarism detection for Python, Java, C++, JavaScript, and 65+ languages. Check against GitHub, Stack Overflow, and web sources.
Check millions of public repositories
Search across the entire internet
Detect code from Q&A sites
Identify AI-generated code
Codequiry is a modern MOSS alternative (Measure Of Software Similarity) for detecting copied code, source code plagiarism, and code similarity. Whether it's for an academic integrity review, a legal or copyright question, or a code audit, Codequiry finds code lifted from GitHub and Stack Overflow and returns detailed results in minutes.
Unlike traditional plagiarism checkers that only compare submissions against each other, Codequiry uses Triple Layer Detection to provide the most comprehensive code plagiarism analysis available. Our advanced system checks across three critical dimensions simultaneously, catching plagiarism that other tools completely miss.
Submission-to-Submission Comparison. Our algorithm compares every submission against every other submission in your batch. Detect collusion rings, shared solutions, and copied code between submissions with advanced token-based matching that catches even heavily modified copies.
Web-Wide Source Search. The game-changer that separates Codequiry from MOSS, JPlag, and Dolos. We search indexed web sources including GitHub repositories, Stack Overflow answers, Chegg solutions, Course Hero, coding forums, tutorial websites, Pastebin, and personal blogs.
Detect AI-Generated Code. The newest and fastest-growing source of unattributed code. Our AI detection engine identifies code generated by ChatGPT, GitHub Copilot, Claude, Gemini, Grok, Cursor, Amazon CodeWhisperer, and other LLM-based code generators with Extremely High Accuracy.
With the explosion of AI coding assistants like ChatGPT, GitHub Copilot, Claude, and Gemini, detecting AI-generated code has become critical for academic integrity, legal review and code audits. Codequiry's AI code detector uses advanced machine learning trained on millions of code samples to identify AI-written code with remarkable accuracy.
Trained on millions of code samples from GPT-5.1, Claude, Copilot, Grok, Gemini, and Cursor to reliably identify AI-generated patterns
Analyzes code entropy, comment patterns, error handling consistency, and stylistic uniformity that reveals AI authorship
Flags when submitted code doesn't match an author's established coding patterns from earlier work
Detects attempts to disguise AI code through dead code insertion, variable renaming, and complex logic restructuring
At the heart of Codequiry's 95%+ accuracy is our proprietary Zeus™ Hyper technology. Unlike traditional tools that compare raw text, Zeus Hyper uses advanced AI-powered semantic analysis to understand what code actually does, not just what it looks like. This allows us to detect plagiarism even when someone renames variables, reorders functions, adds dead code, or uses sophisticated obfuscation techniques.
Using our enterprise code plagiarism checker is simple. Check code for plagiarism in just three easy steps:
Copy and paste the code you want to check for plagiarism into our online code editor. Our code plagiarism detector supports Python, Java, C++, C, C#, JavaScript, TypeScript, PHP, Ruby, Go, Rust, Swift, Kotlin, and 65+ programming languages.
Choose the programming language from the dropdown menu. Our plagiarism checker provides accurate code analysis with proper syntax highlighting for all major languages.
Click "Check for Plagiarism" and our Triple Layer Detection checks the code against peers, web sources, and AI generation patterns. Get detailed similarity scores with source attribution.
Looking for a MOSS plagiarism checker alternative? While Stanford MOSS (Measure Of Software Similarity) was pioneering in 1994, it has significant limitations today. Here's why teams worldwide are switching to Codequiry:
Our programming plagiarism checker is built for anyone who needs to know where code came from, whether that is an academic integrity review, a legal or copyright question, or a code audit. Reviewers can quickly detect code plagiarism, check source code similarity, and identify copied code from online sources. Our system checks against web sources, GitHub repositories, Stack Overflow answers, and uses AI detection to catch AI-generated submissions.
Peer comparison + Web scanning + AI detection in one comprehensive analysis
Catch ChatGPT, Copilot, Claude, and other AI-written code with Extremely High Accuracy
Python, Java, C++, JavaScript, TypeScript, Go, Rust, Swift, Kotlin, and more
Hexagram, built from scratch, and Zeus, optimized for speed
Catches variable renaming, code reordering, dead code insertion, and format changes
Visual comparison with highlighted matches and direct source links for evidence
Our code plagiarism checker supports 65+ programming languages and frameworks, more than many other tools including MOSS, JPlag, and Dolos. Check code for plagiarism in Python, Java, C++, JavaScript, and many more:
Code plagiarism occurs when someone copies source code from another programmer, website, repository, or AI tool without proper attribution. It can be an academic integrity violation, a copyright or licensing problem, or a risk hiding in a codebase. With the rise of AI coding assistants like ChatGPT and GitHub Copilot, detecting AI-generated code has become just as important as detecting copied code. Our code plagiarism detector with AI detection helps identify both copied and AI-written code by analyzing source code against billions of sources and AI generation patterns.
Stanford MOSS (Measure Of Software Similarity) was pioneering when introduced in 1994, but it wasn't built for today's challenges. MOSS compares submitted files; it does not independently search GitHub or Stack Overflow. MOSS cannot detect AI-generated code from ChatGPT or Copilot. MOSS requires command-line submission and email-based results. Codequiry is the premier MOSS alternative offering instant web-based plagiarism detection, real-time results, intuitive interface, web-scale scanning, AI code detection, and support for 65+ programming languages. Experience enterprise-grade plagiarism detection without the limitations of 1994 technology.
Looking to check code for plagiarism with confidence? Codequiry provides the comprehensive solution with Triple Layer Detection. Before you make a call on a submission or a codebase, use our plagiarism detector to check for shared code, web source copying, and AI-generated code. Detect code from Chegg, Course Hero, GitHub, Stack Overflow, and AI tools, with detailed, evidence-based reports.
Reviewers can use our code plagiarism checker to quickly verify submissions across all three detection layers. Detect copied code from GitHub, Stack Overflow, Chegg, previous submissions, and AI assistants. Our plagiarism detector makes it easy to check code of any size for plagiarism, with comprehensive detection trusted by institutions and businesses worldwide.
Get detailed plagiarism reports, batch code checking, team collaboration tools, API access, and advanced features. Experience unlimited code plagiarism detection with our industry-leading platform.