PDF Perfect

    How it works

    How to check that PDF Perfect never uploads your file

    Open a tool, then disconnect from the internet or open your browser's Network tab, and process a PDF. It still works, and no request carries your file. That's because compression, merging, splitting and editing run in JavaScript and a Web Worker on your own device.

    The 30-second offline test

    1. Open a tool, for example Merge PDF, and wait for the page to finish loading.
    2. Turn off Wi-Fi or switch on airplane mode.
    3. Add your PDFs and run the tool.
    4. Download the result. It worked without an internet connection, so the file can't have been sent anywhere.

    Testing Compress? Compress one small PDF while you're still online first. That loads its PDF renderer, and after that it works offline too.

    The Network-tab test

    This works on any computer and shows every request the page makes.

    Chrome, Edge or Brave

    1. Open a tool, right-click the page and choose Inspect, then open the Network tab.
    2. Click the clear button (🚫) so the list is empty.
    3. Process a PDF and download the result.
    4. Look at the new rows. You'll see small analytics requests, but nothing the size of your PDF and no request that contains it.

    Firefox

    1. Press Ctrl+Shift+E (Cmd+Option+E on a Mac) to open the Network panel.
    2. Clear it with the bin icon, then process a PDF.
    3. Check the Transferred column: no request comes close to your file's size.

    Safari (Mac)

    1. Turn on Settings → Advanced → Show features for web developers.
    2. Press Cmd+Option+I, open the Network tab and clear it.
    3. Process a PDF and check the requests in the same way.

    What happens to your PDF, step by step

    1. Your browser reads the file you chose into memory. It stays inside that browser tab.
    2. For merge, split, edit, rotate and extract, pdf-lib copies or changes the pages directly.
    3. For compression, a Web Worker (a background thread in your browser) uses Mozilla's pdf.js to draw each page onto an off-screen canvas, saves it as a smaller image, and pdf-lib builds a new PDF from those images.
    4. The finished PDF is turned into a file in your browser and saved to your device through a normal download. When you close the tab, it's gone from memory.

    What does go over the network

    • The web page and its code, when you first open it.
    • Fonts from Google Fonts.
    • Anonymous usage analytics, such as which tool you used and how big the file was. Never the file itself or its name. Details are in the privacy policy.
    • Anything you type into the Feedback form, if you choose to send it.

    Limits

    • Because everything runs on your device, speed and the largest file you can handle depend on your device's memory and processor.
    • Each PDF can be up to 1 GB. Very large files work best on a computer rather than a phone.
    • Password-protected PDFs aren't supported yet.

    Frequently asked questions

    No. PDF Perfect has no upload server. Your file is read by JavaScript in your browser tab, processed there, and saved back to your device. It is never sent to us or anyone else.

    Mostly. Once a tool page has loaded, merge, split, edit, rotate and extract work without a connection. Compress loads its PDF renderer the first time you use it, so compress one small file while online and it will keep working offline for the rest of that visit.

    Your documents never leave your device, which removes the biggest risk of online PDF tools: a copy sitting on someone else's server. As with any software, use an up-to-date browser on a device you trust.

    The page itself, its fonts and anonymous usage analytics use the network. None of those requests contain your file; you can confirm this by checking the size and contents of each request in the Network tab.