About PDFMaster AI

Most online PDF services follow the same pattern: you upload a file, a server processes it, and you download the result. That model made sense when browsers could not do the work themselves. It no longer does. WebAssembly and modern JavaScript engines are fast enough to merge, split, compress, render and OCR documents locally, on the device that already has the file open.

Keeping the work client-side removes an entire class of risk. There is no upload to intercept, no temporary file left on someone else's disk, no retention policy to trust and no data-processing agreement to negotiate. It also makes the tools faster, because nothing travels over the network twice.

Every tool on this site is built on well-established open-source libraries that run in the browser:

• pdf-lib — creating and modifying PDF documents: merging, splitting, rotating, stamping and metadata editing.
• pdf.js — Mozilla's PDF renderer, used for page previews, rasterisation and text extraction.
• Tesseract.js — WebAssembly OCR for making scanned documents searchable, in English, French and Arabic.
• jsPDF and html2canvas-pro — building PDFs from text, Markdown and HTML.
• mammoth and SheetJS — reading Word and Excel documents.

When you select a file, the browser reads it with the File API into memory. The relevant library performs the operation, and the result is handed back to you as a Blob download. At no point is an HTTP request made with your document's contents.

Browser-based processing has real limits, and we would rather state them than pretend otherwise. Very large files are bounded by your device's memory. Compression that rasterises pages costs you selectable text. Word and Excel conversion recovers structure and content, not Microsoft's exact pagination. Our signature tool produces a visible signature, not a certificate-backed digital one. Each tool page spells out its own trade-offs in the technical details panel.

The guides and articles on this site are written in-house by the people who build the tools. We describe the behaviour of our own software, the file formats we work with, and techniques we have tested. We do not publish generated filler, we do not invent statistics, and we correct pages when a tool's behaviour changes.

Found something wrong or out of date? Tell us on the contact page and we will fix it.

PDFMaster AI is free and has no paid tier. The running costs — hosting, domain and development time — are covered by advertising displayed alongside the tools. Ads are served in clearly separated slots and never interrupt a conversion. We do not sell data; there is no data to sell, because your files never reach us. Our privacy policy explains what our advertising partner can and cannot see.

Feature requests, bug reports and corrections are all welcome at hello@pdfmaster.ai, or through the contact page. Browse the full toolkit on the tools page.