About

About OpenPDF

Last updated: 2026-04-27

What this is

OpenPDF is a free, browser-based PDF toolkit. Every tool — view, merge, split, organize, annotate, sign, compress, watermark, page numbers, add image — runs entirely in your browser using WebAssembly and JavaScript. Your PDFs never leave your device. There is no upload step, no temporary server-side processing, and no copy of your file is kept anywhere outside of your browser session.

Why it exists

The current PDF-tools market is a tax on convenience: Adobe Acrobat costs €15-25/month for editing, the popular freemium sites (Smallpdf, ILovePDF, PDF24, Sejda) gate the obvious feature behind a subscription and require an upload step that leaves a copy of your file on someone else's server, and the desktop alternatives are heavy.

OpenPDF was built by an independent developer in Spain, one tool at a time, with a single rule: every PDF operation that can technically be done client-side must be done client-side. WebAssembly versions of pdf.js, pdf-lib, qpdf and signpdf made this possible. The result is a 10-tool kit that doesn't ask you to trust anyone with your files.

How it is funded

OpenPDF is free, with no signup, no premium tier, no upsell. The site is funded by display ads (Google AdSense) shown around the tools, and by occasional Buy Me a Coffee tips from people who liked the result and wanted to say thanks. There is no plan to add a paywall — the build cost is a one-time engineering investment, and the running cost is small enough that ads cover it comfortably.

Who is behind it

OpenPDF is built and maintained by Marco Bia, an independent developer based in Spain. The site is part of a small portfolio of utility web apps (CompoundVision for finance, AllYouNeed for general utilities, JSONCraft for developers, OpenImages for image work, OpenPDF for PDFs, PingThat for networking). Each one shares the same private-by-default design.

If you would like to talk to a human about a tool, a bug or a feature you wish existed, the Contact page has a feedback form that lands in the operator's inbox within a few hours during EU working days.

Stack and openness

The site is a Vite SPA built in Svelte 5 with TypeScript, with 32 prerendered HTML pages so each tool URL has its own SSR-ready landing page. PDF rendering uses pdf.js; PDF editing uses pdf-lib; signing uses signpdf with the Web Crypto API. Hosting is on Cloudflare Pages. Aggregate analytics use Google Analytics 4 with EU/UK consent gated to "denied" by default.

Editorial independence

Google AdSense pays per impression and click, but does not influence which tools we build, how they work, or what we say in the documentation. There are no sponsored articles, no "best of" lists with affiliate links, and no editorial choices made to favour an advertiser. If a tool exists in OpenPDF, it is because it was useful enough to the operator to build and ship it.