100% free · No sign-up · Runs in your browser
PDF Compressor
Shrink a PDF by choosing a target DPI and JPEG quality. Processing is private and stays on your device.
This free PDF compressor reduces PDF file size in your browser when a portal, job application, or email inbox rejects a large file. Pick a target DPI and JPEG quality, compress, and compare the result before you submit it. The trade-off is honest: pages are re-rendered as images, so the smaller file is no longer text-selectable.
How to use this PDF compressor
- Add one PDF from your device (up to 100 MiB and 1,000 pages).
- Pick a target DPI: Screen (72), Balanced (96), or Print (150).
- Adjust JPEG quality — lower means smaller and softer. 75 is a good default.
- Click Compress PDF, then download the result if it is smaller.
How compression works
Each page is re-rendered locally at your chosen DPI and re-encoded as a JPEG at your chosen quality. Lower DPI and lower quality produce smaller files. If the result ends up larger than the original, the tool tells you instead of pretending it helped.
Example: A 22 MB phone scan of a signed lease often drops to a few megabytes at 96 DPI and quality 75 — small enough for most email attachments and upload forms.
Because pages become images, copy and paste of text will not work in the compressed file. Keep the original if you need selectable text.
Compression level guide
These settings match the controls in the tool. Savings vary by page count and how many photos the PDF holds — text-heavy scans usually shrink more than files that are already optimized.
| Level | DPI | JPEG quality | Typical use |
|---|---|---|---|
| Screen | 72 | About 60-75 | Email and online forms when size matters most |
| Balanced | 96 | About 75 | Everyday applications and school packets |
| 150 | About 80-90 | When you still need clearer detail on paper |
Size limits for forms, email, and uploads
Many US government and hiring portals cap uploads at a few megabytes. Compress a PDF before you upload so the form accepts the file on the first try.
Email providers often limit attachments to about 20-25 MB total. Reduce a PDF for email when a scanned application, offer packet, or tax document is too heavy to send.
Some forms still ask for files near 100 KB for ID scans. Start with Screen DPI and lower quality, then raise quality if text becomes hard to read.
Files are rendered and rebuilt locally in your browser, so sensitive documents like tax returns and medical bills are never uploaded or stored after you leave the page.
Frequently asked questions
Can I compress a PDF for free without watermarks?
Yes. Compression runs in your browser with no account, no watermark, and no upload.
Will the compressed PDF still have selectable text?
No. Pages are re-rendered as images to reach smaller sizes, so text is no longer selectable. Keep your original for copying text.
How small can my PDF get?
It depends on the content. Photo-heavy scans shrink the most; already-optimized PDFs may barely change, and the tool warns you if the result is larger.
Is my PDF uploaded to a server?
No. Rendering and rebuilding happen entirely in your browser. Nothing is uploaded or stored after you leave or clear the page.
Which setting should I try first?
Balanced (96 DPI, quality 75) suits most documents. Drop to Screen for strict size limits, or raise to Print if the result looks soft.
More free PDF tools
Related: PDF merger, PDF splitter, PDF to image, and the PDF Tools hub.
PDF is an open format documented by ISO 32000 PDF standard.