Compress PDF
Reduce the file size of a PDF for email attachments and upload limits. Lossless mode repacks and recompresses the file while keeping text selectable; strong mode re-renders every page as an optimized image for much larger savings on scanned documents.
The interactive tool loads here when JavaScript is enabled. Files are processed locally in your browser.
How to use Compress PDF
- Choose a PDF up to 20 MB.
- Pick Lossless (keeps text and quality) or Strong (smaller, image-based pages).
- For Strong mode, choose the resolution and image quality.
- Compress, compare the sizes and download.
Features
- Lossless mode recompresses streams and packs objects using qpdf compiled to WebAssembly.
- Strong mode renders pages at 72–150 DPI and stores them as JPEG.
- Shows the original size, new size and percentage saved.
- If compression does not help, the tool keeps your original instead of a bigger file.
Supported formats and limitations
Input and output: PDF.
- Strong mode turns pages into images, so text is no longer selectable.
- Some PDFs are already optimised and cannot be made smaller; the original is kept in that case.
- Password-protected PDFs must be unlocked first.
Frequently asked questions
Which mode should I choose?
Use Lossless for text documents you still want to search and copy from. Use Strong for scanned pages and photo-heavy PDFs that must get much smaller.
Will text remain selectable after compression?
In Lossless mode, yes. Strong mode turns each page into an image, so text can no longer be selected; use PDF OCR afterwards if you need searchable text.
Are my PDFs uploaded?
No. Both modes run entirely in your browser.