About Foldr

Foldr is a set of PDF tools built around one constraint: nothing gets uploaded. Merging, splitting, compressing, converting, watermarking, and repairing PDFs are all common tasks that most existing tools solve by having you hand your document to a remote server. Foldr solves them entirely inside your browser instead, using WebAssembly libraries like pdf-lib and pdf.js.

That means the tools work offline once loaded, there's nothing to sign up for, and there's no file size cap imposed by a server — the only limit is your own device's memory.

You can read the technical details of how the client-side processing works on the how it works page, or head back to the full list of tools.