Large PDFs are slow to email and sometimes rejected by upload forms. This tool shrinks a PDF by re-rendering its pages as optimised images, cutting the size significantly — especially for scans and image-heavy documents.
It all runs in your browser, so your document is never uploaded.
How to use Compress PDF
Using Compress PDF takes only a few seconds and just four simple steps — no sign-up, no software, and nothing to learn:
- Upload a PDF: Add the document you want to shrink.
- It's compressed: Each page is re-rendered and optimised to reduce size.
- Compare: See the original versus compressed file size.
- Download: Save the smaller PDF.
What you can do with Compress PDF
Compress PDF is built to do one job well, and gives you everything you need to get it exactly right:
Real size reduction. Especially effective on scanned and image-heavy PDFs.
Private compression. Runs in your browser — nothing is uploaded.
No watermark. Your compressed PDF comes back clean.
Free and unlimited. Compress as many PDFs as you need.
Smaller PDFs without an upload
Most PDF compressors send your file to their servers. This one works entirely in your browser, so confidential documents stay private while still slimming down enough to email or upload.
Whether you need it once or every day, Compress PDF keeps the process quick and predictable. Because it focuses on a single task, there are no crowded menus to wade through — you open the page, set what you need, and get your result. That simplicity is exactly why a dedicated PDF tool beats a heavyweight editor for a job like this.
Everything runs in your browser
Unlike most online tools, Compress PDF never uploads your PDF to a server. The moment you choose a file, it is processed right here in your web browser using your own device's power. Nothing is sent over the internet, nothing is stored, and nothing is shared with anyone.
That gives you two real advantages. First, it is private: sensitive documents, ID photos and personal files never leave your computer or phone. Second, it is fast — there is no slow upload or download round-trip, so even large files are handled almost instantly. And it is completely free, with no watermark added to your result and no account required.
Tips for the best results
- Start from the highest-quality original you have — the better the input, the better the result from Compress PDF.
- Check the exact requirement — size, dimensions, or format — before you begin, so you only need to do it once.
- Real size reduction: Especially effective on scanned and image-heavy PDFs.
- Private compression: Runs in your browser — nothing is uploaded.
- Everything is repeatable — if the result isn't quite right, just adjust the settings and run it again. Nothing is uploaded, so you can try as many times as you like.
Frequently asked questions
Will the text stay selectable?
No — pages are flattened to images during compression, which is what enables the size reduction. Keep the original if you need selectable text.
How much smaller will it get?
It varies. Scanned and photo-heavy PDFs shrink the most; PDFs that are already optimised may compress only a little.
Is my PDF uploaded?
No — compression happens in your browser.
Is Compress PDF free to use?
Yes — Compress PDF is completely free. There is no account to create, no subscription, and no watermark added to your result. Use it as many times as you need.
Do I need to install anything?
No. Compress PDF runs entirely in your web browser on any modern device — Windows, Mac, Android or iPhone. There is nothing to download or install.
Ready to start? Scroll back to the top, drop your PDF into Compress PDF, and download the finished file in seconds — free, private, and right inside your browser.