Compress a PDF without uploading it
Shrink scanned PDFs dramatically — everything stays on your device.
Processed on your device — nothing is uploaded. Works offline.
How to compress a PDF without uploading it
- 1Choose one or more PDFs.
- 2Pick a level. Strong (96 DPI) gives the smallest file, Balanced (144 DPI) suits most scans, Light (200 DPI) keeps fine detail, and Lossless only tidies the file structure so text stays selectable.
- 3Click Compress. The before and after size is shown for every file before you download.
Every step runs in this tab. The site has no upload endpoint, and the page's security policy forbids the browser from contacting any other server — see how that is enforced.
When you'd use it
Email attachment limits
A 40 MB scan that has to get under a mail server's cap.
Portals with size caps
Court, government and university upload forms that reject anything over a few megabytes.
Archives
Years of scanned records that take far more space than they need to.
Good to know
- Strong, Balanced and Light re-render every page as an image, like a good scan, so text is no longer selectable. Lossless keeps the text but gains far less.
- Scanned documents typically shrink 5–15×; digitally created PDFs with little imagery compress much less.
- Each file's before and after size is shown, so you can try another level before downloading.
Don't trust us — test us
“Your files never leave your device” is a claim every PDF site makes. Here it is checkable in under a minute, three different ways:
- Watch the network.Open your browser's developer tools, switch to the Network tab, then run the tool. The only requests you will see are the site's own files — none of them carries your document — and once the app is cached there are no requests at all.
- Pull the plug. Load this page, turn off your wifi or switch on airplane mode, then use the tool. It keeps working, because there is no server involved and nowhere to upload to.
- Read the headers. The response headers for this page include a Content-Security-Policy with
connect-src 'self': the browser itself refuses to send anything to another host, whatever the code asks.
The full privacy model, including what we can't protect you from →
Guide
How to edit a PDF without uploading it
Most 'edit a PDF' jobs are one of seven things, and all seven can be done in your browser without the file leaving your machine. Which tool for which job, and the honest answer on editing the text itself.
Frequently asked questions
How much smaller will my PDF get?
Scanned documents typically shrink 5–15×. The compressor re-renders pages as optimized images, so results depend on content and the level you pick. The before/after size is shown before you download.
Will text still be selectable after compression?
In Strong/Balanced/Light mode, pages are re-rendered as images, so text is no longer selectable — like a good scan. For digitally-created PDFs where you need selectable text, use Lossless mode (smaller gains, structure-level cleanup only). We tell you this before you run it because most tools don't.
Are my files uploaded to a server?
No. All processing happens inside your browser using WebAssembly and JavaScript. Our server only serves the app itself — there is no endpoint that can receive files. You can verify this in your browser's network tab, or turn off your wifi after the page loads: everything still works.
Does it work offline?
Yes. After your first visit the whole app is cached by a service worker, so the page loads and every tool works with no connection at all. Load the page, switch on airplane mode, and carry on.
Is there a file size limit?
No hard limit — your device's memory is the ceiling. Files up to a few hundred MB work well on a typical laptop. Very large files may be slow or fail on low-memory devices; nothing is ever truncated silently.
Do I need to create an account?
No. No account, no email, no cookies. The free tools are simply free.
Which browsers work?
Current Chrome, Edge, Firefox and Safari, on desktop and on phones. Phones have less memory, so very large files are better handled on a laptop.