Plagiarism Checker X vs Proofademic

Plagiarism Checker X is Windows desktop software for checking documents and text against published web pages for plagiarism and similarity. Its online checker compares content with more than 16 billion pages. Bulk Comparison examines multiple documents in repositories, while Side-By-Side Difference places content in two windows to locate matching text. An AI detector indicates whether writing may have come from an AI tool or a human. A readability checker analyzes reading levels, extracts keywords and assesses difficulty. Reports mark matches with colors and references and can export to Word, PDF or Excel. The software accepts Word, PDF, text and other textual formats. Its interface is available in English, Spanish, French, German, Italian, Dutch and Portuguese, with content support for hundreds of languages. The maker says documents remain on the user’s computer and customer content is not copied, stored or sold. Basic is free with limited words and a daily search limit. Professional costs $39.95, paid once; Business costs $147.95, paid once.

Proofademic analyzes submitted writing for AI-generated content and plagiarism, producing an overall score and sentence-by-sentence breakdown. Its listed checks include AI text, ChatGPT, paraphrase, multilingual and plagiarism detection, as well as Batch Scan. Proofademic says it reviews essays, research papers, articles and reports in 23 languages, with model coverage including ChatGPT, GPT-5, Claude and Gemini. Batch Scan lets teams upload documents, sort results by risk, inspect sentence-level evidence and export reports. Developers and platforms can use the AI Image Detector API; a browser-based image detector for individual users is described as coming soon. Proofademic says submitted text is processed automatically, is not used for model training or resale, and is not reviewed by people. It reports a 0.2% document false-positive rate in an evaluation of 4,200 fully human-authored academic texts, while advising that results support human review. The Free plan is free and includes 1,000 words and a 3-day trial. Paid plans are $15 a month for Essential, $25 a month for Premium and $45 a month for Professional.