PDFdays

    Last updated November 1, 2026

    How PDFdays Keeps Your Files Private

    Most online converters upload your file to their server, convert it there and send it back. PDFdays works differently: the conversion happens inside your own web browser, on your own device.

    Your files are not uploaded to our servers. Nobody at PDFdays can see them, and there is no copy of them anywhere for us to keep or delete.

    1. What happens when you convert a file

    • You choose a file. Your browser reads it from your device into the memory of this tab. It is not sent over the internet.
    • The page converts it. Code that already downloaded with the page does the work on your computer or phone.
    • You download the result. The new file is created in your browser and saved straight to your device.
    • You close the tab. The files are cleared from the page's memory. Reloading the page or removing a file does the same.

    2. The technology we use

    Everything runs as JavaScript in your browser, using these open-source tools and built-in browser features:

    • pdf.js (by Mozilla) draws each PDF page so it can be saved as a JPG, PNG or other image. It runs in a background worker inside your browser.
    • pdf-lib creates new PDFs from images and merges or splits PDFs by copying pages as they are, so text stays sharp.
    • The HTML Canvas built into your browser decodes and re-encodes images such as JPG, PNG, WebP, BMP, SVG and GIF.
    • UTIF reads and writes TIFF images, and fflate packs many results into one ZIP file.

    3. What still uses the internet

    Your browser downloads the website itself from us: the page, its code, fonts and the font data pdf.js needs to draw some PDFs correctly. These are downloads to your device only. Your files are never part of them.

    PDFdays is free, and to cover our costs we may show ads. Ads and cookies are explained in our Privacy Policy and Cookie Policy. Ad services never receive your files.

    4. What we save on your device

    Only your choice of language and light or dark theme, so the site remembers them next time. Your files and converted results are not saved by PDFdays — the downloads you choose to keep are saved by your browser to your device.

    5. Check it yourself

    Open your browser's developer tools (press F12 on most computers), go to the Network tab and convert a file. You will see the page loading its own code, but no request that sends your file anywhere.

    6. Good to know

    • Because your own device does the work, very large files or big batches depend on its memory and speed. A modern computer handles more than an older phone.
    • It works in current versions of Chrome, Edge, Safari and Firefox on Windows, Mac, Linux, Android and iPhone.
    • Converting a PDF to an image turns text into a picture. Keep the original PDF if you need to copy text.

    7. Contact us

    If you have any questions about this page, your data or your rights, email us at support@pdfdays.com or use our Support page. We aim to reply within a few business days.

    Email: support@pdfdays.com

    Website: https://pdfdays.com