Compress a PDF
Make scanned documents and photo-heavy PDFs small enough for email and upload forms. You choose the resolution and JPEG quality and see the size before and after. Everything runs on your device.
Drop PDF files here
or
Files are processed on your device. Nothing is uploaded.
0 bytes uploaded
Pages that are mostly images are redrawn at this resolution and JPEG quality. Pages with only text are copied unchanged.
How to compress a PDF
- 1
Drop one or more PDFs in, or click “Choose files”.
- 2
Pick a resolution and JPEG quality. 150 DPI and 70% suit most scans.
- 3
Compare the size before and after, then download the smaller PDF.
What PDF compression can and cannot do
Most of the weight in a large PDF comes from pictures: scanned pages, photos and high-resolution illustrations. This tool redraws pages that are mostly images at the resolution you pick and saves them as JPEG, which often makes scans several times smaller.
PDFs that are mainly text barely shrink. Text is already stored very compactly, so there is little to gain, and those pages are copied unchanged. A page that is redrawn becomes a single image, which means its text can no longer be selected or searched. If the result is not smaller than your file, you get the original back.
Private by design
- Processed on your device — files are never uploaded.
- Works offline once the page has loaded.
- No limits on file count or size beyond what your device can handle.
Frequently asked questions
Why did my PDF hardly get smaller?
Text-only PDFs, such as reports exported from a word processor, are already compact. The tool only redraws pages where large images make up most of the size, so documents without them stay almost the same.
What happens if the compressed file is bigger?
Then the original is kept and the list shows “already compact, original kept”. You never end up with a larger file than the one you started with.
Which resolution and quality should I choose?
150 DPI with 70% quality keeps scans easy to read on screen. Use 72 DPI for the smallest files, or 300 DPI when small print must stay crisp.
Can I still select text after compressing?
Not on pages that were redrawn, because they become images. Pages with only text are copied unchanged and stay searchable. If you need selectable text everywhere, keep the original.
Are my documents uploaded?
No. Pages are rendered with the open-source PDF.js engine and rebuilt in your browser. The PDF never leaves your device.