Compress PDF
Make PDFs small enough for email, portals and upload forms. Images inside the PDF are resized and re-encoded while text stays sharp and selectable. Your files never leave your device.
Results appear here. Files are processed on your device and never uploaded.
How it works
- Add PDFsDrop one or several files. Nothing is uploaded; your browser reads them directly.
- Choose a levelRecommended suits most documents. Strong targets tight upload limits. Extreme redraws each page as an image for the smallest possible file.
- CompressEvery photo and scan inside the PDF is resized to a sensible resolution and re-encoded as JPEG. Text, vector graphics and fonts are left untouched.
- DownloadYou see the size before and after. If a file cannot get smaller, the original is kept.
Why PDFs get so big
Text is tiny: a hundred pages of words may take less than 200 KB. What makes PDFs heavy is images. A single phone photo can be 4,000 by 3,000 pixels and several megabytes, and scanners often save every page as a full-colour image at 600 DPI. When those pages are printed or viewed on screen, most of that detail is wasted. Reducing images to about 150 DPI, the recommended level, is still sharp on screen and on an office printer, and it typically cuts photo-heavy PDFs by 60 to 90 percent.
The levels map to image resolution and JPEG quality: Light keeps about 220 DPI at high quality, Recommended about 150 DPI, and Strong about 100 DPI with lower quality. Extreme is different. It renders each whole page to a single image, which also compresses text-heavy PDFs, but the text is no longer selectable or searchable. Run OCR PDF afterwards if you need both.
Tips for hitting an upload limit
- Start with Recommended. If the result is still above the limit (often 1, 2 or 5 MB), try Strong, then Extreme.
- A PDF made only of text and vector drawings is usually already small. Compression mostly helps scans and photos.
- Split very long documents into parts with Split PDF when a portal limits each file.
- Keep your original. Re-compressing an already compressed PDF again gives small gains and lowers image quality.
What stays the same
Page count, page sizes, text, links, bookmarks and form fields are preserved for the Light, Recommended and Strong levels, because only the image data changes. Transparent images keep their transparency masks. Images in unusual colour spaces, such as CMYK print files, are left as they are rather than risk a colour shift.
Frequently asked questions
Is it safe for confidential documents?
Yes. Compression runs entirely in your browser. The PDF is never uploaded, stored or seen by anyone else.
Why did my file barely shrink?
It probably contains mostly text and vector graphics, which are already efficient, or its images were compressed before. Try Extreme if you only need to view or print it.
Can I compress password-protected PDFs?
Not directly. Open the file with its password, save or print a copy without protection, then compress that copy.
Is there a size limit?
No fixed limit. Very large files depend on your device's memory; files of a few hundred megabytes work on most laptops.