100% local — press F12 to verify

Compress PDF to 500KB online.

Free. No sign-up. Exactly 500KB — your files never leave your browser.

  • 100% Local ProcessingYour files stay on your device
  • Zero UploadsNo tracking, nothing leaves
  • Fast & EfficientSeconds, right in your browser
  • Free Batch ModeNo limits, no registration
How it works →

Drop your PDF here

or click to browse — multiple files = free batch mode

Target size:
Privacy First

Your files never leave your device. Total privacy, guaranteed by design.

Lightning Fast

Processing happens instantly in your browser. No waiting, no queue.

Verifiable

Press F12 and watch the Network tab: zero uploads, every single time.

Always Free

Every tool, every batch, no hidden costs. Use unlimited.

How do we keep your files private?

Do you upload my files to a server?

Never. PDF Slim runs entirely in your browser — pages are rendered and re-encoded on your own device. Your files don't touch our servers for even a second.

How can I verify that myself?

Press F12 to open Developer Tools, click the Network tab, then compress a PDF. You'll see zero uploads. In fact, you can disconnect from the internet and compression still works.

Do you track me or use cookies?

No cookies, no tracking pixels, no analytics. There's nothing to sign up for and nothing stored about you — the only thing saved is a local counter of bytes processed on your own device.

Why compress to 500KB?

Why exactly 500KB?

Many court e-filing systems, corporate email gateways and older web forms cap attachments at 500KB. At this size, multi-page scans stay crisp — quality loss is barely visible.

Will my document still look good?

Court e-filing and corporate mail gateways often enforce a 500KB per-attachment cap.

Is it really free and unlimited?

Batch mode included: drop ten files, get ten files back — all under 500KB, all free.

More free tools you might need

and counting — every byte stayed on a device like yours.