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100% in your browser
Files stay on your device. No uploads to our servers — ideal for confidential documents.
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Compress PDF Online
Reduce file size for faster sharing and smaller archives. Shrink PDF file size with adjustable compression. Runs locally — great for email attachments and cloud storage limits.
No document data Download No Sign-up Required
01 / add file
Drop your PDF here
Choose one document to make lighter and easier to share.
Select PDF files
or drop PDF files here
Single file · Max 256 MB
Core processing stays in this browser after the page loads. Large files use device memory and may run slower.
Compress PDF Online
Shrink PDF file size with adjustable compression. Runs locally — great for email attachments and cloud storage limits.
Quick answer
How can I compress a PDF without uploading it?
Select your PDF, choose a compression level, and hit compress. The file processes in your browser so it never uploads to our servers. Savings vary by content; text-heavy PDFs often compress more than scans.
Privacy by default
Select your PDF, choose a compression level, and hit compress. The file processes in your browser so it never uploads to our servers. Savings vary by content; text-heavy PDFs often compress more than scans.
How to compress a PDF
How to compress a PDF
Three steps to a smaller file
- 01
Upload your PDF
Add a PDF to compress.
- 02
Choose compression
Pick a level that balances size and quality.
- 03
Download
Save the smaller PDF to your device.
Why use our PDF compressor?
Why use our PDF compressor?
Smaller files, same workflow
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No account required
Get started instantly. No registration, no credit card, no watermarks on exports.
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Fast local processing
PDF work runs locally in your browser for quick results — no round-trip to a server.
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Works everywhere
Use Chrome, Firefox, Safari or Edge on desktop and mobile — no install needed.
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Privacy by design
We never store your files. Processing happens in memory in your tab.
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Core tools free
Use without limits tied to an account — built for everyday document tasks.
PDF Compression FAQ
PDF Compression FAQ
Quality, privacy, and limits
Will compression damage quality?
High compression may reduce fidelity; use lower settings for important documents.
Is there a file size limit?
Very large files may hit browser limits — try a smaller PDF if issues occur.
Do you store my PDF?
No — compression runs entirely in your browser.
Can I compress for email?
Yes — aim for under typical email attachment limits.
Scanned PDFs?
Scanned pages may compress less than text-based PDFs.
Is it free?
Core compression is free with no account required.
Learn before you process
PDF guides for this workflow
Get the answer, understand the trade-offs, then use the focused tool when you are ready.
How to merge PDF files online
Combine PDFs in the right order, keep bookmarks and form fields, and check the result before you share it.
Read the merge guide
How to merge PDF files on a phone
Select, order, merge and verify PDFs from a mobile browser, combine photos and scans first, and avoid the memory and download problems that catch people out on phones.
Read the mobile guide
How to compress a PDF online
Reduce PDF size for email and uploads without losing quality: the three compression levels, readability checks and size-limit fallbacks.
Read the compression guide
Comparing PDF tools? FreePDFKit vs iLovePDF · FreePDFKit vs Smallpdf · Browser-local vs cloud PDF tools
Related PDF tools
Verify it yourself
Your file is not uploaded. Here is how to check.
The core tools run inside your browser tab, so a document you open here is not sent to FreePDFKit or to anyone else. You can confirm that in about a minute.
- Step 1
Open the tool and let it load
Wait until the page has finished loading.
- Step 2
Open your browser’s developer tools
Press F12 (or Cmd+Option+I on a Mac) and switch to the Network tab.
- Step 3
Run the tool on a test file
Choose a non-sensitive file of the type the tool accepts and process it as usual.
- Step 4
Look for a request that carries the file
You will not find one. The page loads its own scripts, then the work happens in your browser.
What backs this up
- Open-source libraries in the page. PDF handling uses libraries such as pdf-lib and Mozilla’s PDF.js, which run in your browser.
- No PDF endpoint on the server. The only server routes are the contact form and the social-preview image generator.
- A restrictive security policy. The site’s Content-Security-Policy limits the fetch and XHR connections page scripts can make to our own origin, Google analytics services and Cloudflare’s anti-spam check.
More detail in the privacy policy and how this compares with other no-upload options.