Protect confidential drafts and identity documents before sharing.
Stamp diagonal or tiled text watermarks across your PDF pages locally in your browser with full control over opacity, rotation, and color.
Is Instant Client-Side PDF Watermark Studio safe for confidential documents?
Yes. MantaPDF processes your PDFs 100% locally inside your browser memory using WebAssembly — zero bytes are ever uploaded to a server.
Does this PDF tool work offline without an internet connection?
Yes. Once loaded or installed as a PWA on your phone or laptop, all PDF operations run completely offline at native speed.