Compress a PDF
Shrink large PDFs so they're easier to email and upload. You'll see the exact size before and after — and if we can't make it smaller, we'll tell you.
How it works
How to compress a PDF
- 1
Open your PDF.
- 2
Choose a compression level (and mode).
- 3
Click Compress PDF, compare sizes and download.
Features
Why use our Compress PDF tool
Honest results
Exact before/after sizes. If the result isn't smaller, you keep your original.
Keeps text & links
The default mode only recompresses images, so text stays selectable.
Maximum mode
Rasterize pages for the smallest possible file when quality matters less.
Guide
About Compress PDF
Big PDFs bounce off email limits and upload forms. Most of their size usually comes from embedded photos and scans, so the recommended mode recompresses those images to a sensible resolution while leaving text, links, bookmarks and forms untouched.
You always see the exact size before and after. If a file is already optimized and can't get meaningfully smaller, the tool says so and you keep your original instead of a bigger copy.
Tips for best results
- Start with Balanced; use Strong for email attachments with strict limits.
- Maximum compression rasterizes pages: text stops being selectable, so use it only when size matters most.
- Text-only PDFs are usually already small — compression won't change them much.
How your file stays on your device
Compress PDF runs entirely inside your web browser. When you choose a file, your browser reads it into memory on your own device, a background Web Worker does the processing, and the result is handed straight back to you as a download. There is no upload step, no server that receives your document and no copy kept anywhere — close the tab and it is gone. That makes it safe for contracts, IDs, medical letters and anything else you would rather not send to a stranger's server. How in-browser processing works
FAQ
Compress PDF: frequently asked questions
How much smaller will my PDF get?
It depends on the content. Image-heavy PDFs (scans, photos) often shrink 50–90%. Text-only PDFs are usually already compact.
What does 'maximum compression' do?
It renders every page as an image and rebuilds the PDF. Files get much smaller, but text is no longer selectable and links, forms and bookmarks are lost.
Are my files uploaded to a server?
No. Compression happens entirely inside your browser using JavaScript and WebAssembly. Your files never leave your device, and nothing is stored after you close the tab.
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