Free & Open Source

Someone sent you a PDF. Send it back done.

Open. Fix. Save. Done.

MegaPDF does the one job most people actually have with a PDF: check the boxes, drop in your signature, and save it back — without an account, a subscription, or your document ever leaving your device.

Download for Windows View the source

Android and iPhone / iPad apps are in testing now — Google Play and App Store releases are on the way.

MegaPDF on iPhone showing a rental agreement with checked boxes and a signature

✓ Check any box

Real form fields and plain printed squares alike — MegaPDF recognizes drawn checkboxes that other apps treat as decoration.

✎ Sign like you mean it

Draw your signature or photograph the one on paper — the white background disappears. Place it, move it, resize it until it sits right on the line.

💾 Save without fear

Every save is verified before it touches your original, so a failed write can never corrupt the file someone sent you.

🔍 Find any word

Search the whole document as you type. Every match lights up, the counter tells you how many, and one tap walks you to the next.

🔒 Private by design

Zero permissions, zero network access, zero analytics. There is no server for your documents to go to — and the code is open, so anyone can check.

See it in action

The real app, doing the real job — no mockups.

A rental agreement with two checked boxes and a handwritten MegaWoman signature — Checked and signed in under a minute

Searching a rental agreement for the word rental, with three matches highlighted and a 1 of 3 counter — Find any word, on every page

The signature library sheet — Your signatures, saved on your device

Drawing a signature with a finger — Draw it once, use it everywhere

The home screen with recent documents — No account. No cloud. No tracking.

One engine, three platforms. Documents you sign on Windows open perfectly on Android and iPhone — and vice versa. Windows 11 · Android · iOS / iPadOS