Paperpal vs PDF.chat

Paperpal is an AI research and academic writing workspace for students and researchers, combining writing help, citation tools, and academic checks. Users can upload references and PDFs, ask questions, and receive cited findings from more than 300 million verified research articles. Writing tools cover academic suggestions, paraphrasing, tone changes, word reduction, grammar, proofreading, and citation formatting. Its checker suite looks for plagiarism and AI-writing patterns, checks references, and assesses journal submission readiness. Paperpal runs on the web and as a browser extension; it also offers a Microsoft Word add-in and browser-extension support for Google Docs and Overleaf. The free plan includes 200 language suggestions, five generative AI uses per day, 7,000 plagiarism-check words per month, and five daily AI-detection scans of up to 1,200 words each. Prime costs $144 a year billed annually, or $25 a month billed monthly. Pro costs $348 a year billed annually, or $59 a month billed monthly. Paperpal says it does not train its AI models on user documents, uploads, or personal information, and allows document deletion.

PDF.chat lets users upload documents, ask questions, and receive answers cited to exact pages in over 100 languages. It accepts PDFs, Word and PowerPoint files, text files, and images, including scanned or photographed documents that its OCR models read on its own infrastructure. Long documents are indexed so questions can retrieve relevant pages from reports, textbooks, and dockets. Users can compare Claude, GPT, Gemini, Llama, and DeepSeek answers side by side in one chat, then export results as plain text, Markdown, DOCX, searchable PDF, CSV, or JSON. The service runs in a browser without a download or installation. Its REST API ingests documents, returns per-page text and metadata, and supports chat with page citations; API use is metered per page. The Free plan costs nothing, with pages resetting at midnight UTC and no credit card required. Starter costs $5 a month and includes 750 pages per month. PDF.chat says files are automatically deleted shortly after processing and are not sold, shared, or used for training; on paid tiers, relevant passages may be sent to third-party AI providers.