Compress PDF reduces the size of a PDF document so you can attach it to an email, upload it to a job portal, a government form or a university website that has a strict size limit. Most oversized PDFs are large because of scanned pages and high-resolution photos, and that is exactly what this tool targets.
The compressor first tries a lossless optimization of the file structure. It then rebuilds each page as an optimized JPEG image at the level you pick and gives you whichever version is smaller. Scanned documents usually shrink by 50–90%.
How to use the Compress PDF tool
- Click the upload box or drag your PDF onto it.
- Pick a compression level: Light keeps the most detail, Recommended suits most documents, and Strong gives the smallest file.
- Press Compress PDF and wait while each page is processed. A progress bar shows how far along it is.
- Compare the old and new sizes, then click Download to save the compressed PDF.
Features
- Three compression levels, so you choose between quality and size.
- A lossless structure pass that keeps text selectable whenever it is enough.
- Works well on scanned documents, photo-heavy reports and presentations exported to PDF.
- No sign-up, no watermark and no daily limit.
- Works on phones, tablets and desktops in any modern browser.
Tips for best results
If you need to hit an exact limit such as 100 KB or 200 KB, start with Recommended and switch to Strong if the file is still too big. When a document is mostly typed text, it is often small already, and the lossless pass keeps the text sharp and searchable. When the image-based pass wins, the pages turn into pictures, so text can no longer be selected. Keep your original file if you will need to copy text from it later.
Compatibility and limits
The Compress PDF tool works in current versions of Chrome, Edge, Firefox, Safari, Opera and Samsung Internet, on desktop and mobile. Processing speed depends on your device: a typical document finishes in a few seconds, while files with hundreds of pages or very large scanned images may take longer on older phones. Encrypted (password-protected) PDFs must be unlocked before they can be processed. Your original file is never changed, because the result is always saved as a new download.
Privacy: your files never leave your device
Your PDF is opened and processed by JavaScript running in your own browser, using open-source libraries we host ourselves. The document is never uploaded to our server or anyone else's. Once the page has loaded, the tool even works without an internet connection. Close the tab and the file is gone from memory.
Frequently asked questions
Is it safe to compress confidential PDFs here?
Yes. The whole compression process runs in JavaScript inside your browser. Your PDF is never uploaded, so nobody else can see it, not even us.
How much smaller will my PDF get?
It depends on the content. Scanned pages and photos often shrink by 50–90%. PDFs that contain only text are already compact, so they may shrink only a little.
Will the text stay selectable?
When the lossless optimization gives the smaller file, yes. When the image-based recompression is used, each page becomes an image, so text is no longer selectable or searchable.
Can I compress a password-protected PDF?
Remove the password first. Encrypted PDFs cannot be read until they are unlocked with the correct password.
Is there a file size limit?
There is no fixed limit. Very large files (hundreds of pages) depend on your device's memory and may take longer on older phones.