Compress a PDF
Two honest modes: Lossless restructures the PDF internals (object streams) with zero quality change — typically 5–30% smaller. Strong re-encodes each page as an optimized image — much smaller files, ideal for scanned documents, but text is rasterized. We show you the before/after size so you decide.
How to use the Compress PDF tool
Select or drag the PDF you want to shrink.
Pick Lossless (identical quality) or Strong (maximum reduction).
Click “Compress PDF”, check the new size and download.
Your files stay on your device
This tool runs entirely in your browser using JavaScript and WebAssembly. There is no upload step and no server processing — open your network panel and check: zero document data is transmitted. It even keeps working offline once the page has loaded.
Frequently asked questions
Why does “lossless” sometimes only save a little?
Lossless mode rewrites the PDF structure without touching images or fonts. If a PDF is already well-built, there is little structural waste to remove. For big savings on image-heavy files, use Strong mode.
Will I lose text selection with Strong compression?
Yes — Strong and Extreme modes convert each page into an optimized image, so text can no longer be selected. Use Lossless if you need selectable text, or run OCR afterwards.
Is there a file size limit?
No. Because compression runs on your device, there are no server limits — a 200 MB scan works fine, it just takes a bit longer.
Is it safe to use this tool with confidential documents?
Yes — and verifiably so. PDFAgent has no upload step: your file is processed by JavaScript running in your own browser and never leaves your device. You can open your browser’s network panel (or even go offline after loading the page) and confirm that no document data is transmitted.
Related guides
- How to Make a PDF Smaller for WhatsApp (Free, No Upload) WhatsApp won't send your PDF or it arrives blurry after compression? Here's how to shrink a PDF the right way before sending it on WhatsApp — free, private, in your browser.
- How to Print 2 or 4 PDF Pages Per Sheet (Save Paper & Ink) Fit 2 or 4 PDF pages onto each printed sheet to save paper and ink. Here's how to bake it into the PDF so it prints right anywhere — free, in your browser.
- How to Remove a Password from a PDF You Own (Free) Tired of entering the same PDF password every time? Here's how to unlock a PDF you legitimately own — free, private, and without uploading anything.
Related tools
Popular size limits
Preset pages for the limits upload forms ask for most: