How to compress a PDF
- Drop a PDF into the box or click to select it.
- Choose a method: Strong (lossy) or Lossless.
- For Strong, pick a resolution (110 DPI is recommended) and an image quality.
- Click Compress PDF, compare the before and after sizes, then download.
What you can do with Compress PDF
- Strong compression
- Re-renders every page as a JPEG at the resolution you pick, which can shrink scanned and photo-heavy PDFs dramatically.
- Lossless mode
- Re-saves the PDF with compressed object streams, leaving text, links and quality untouched for modest savings.
- Resolution and quality control
- Choose 72, 110, 150 or 200 DPI and a quality from 20 to 95 to trade size against sharpness.
- Before and after stats
- See the original size, the new size and the percentage saved, with a hint if the file did not get smaller.
- Keeps page size and title
- Compressed pages keep their original dimensions, and the document title is carried over to the new file.
Lossy vs lossless PDF compression
The two methods work very differently. Strong compression draws each page to an image and stores it as a JPEG, which is how scanned documents and image-heavy PDFs drop from tens of megabytes to a few. The trade-off is that the result is a picture of each page: text is no longer selectable or searchable, and links and form fields are removed. Lossless mode keeps the PDF's structure exactly as it is and only rewrites it more compactly, so savings are usually small but nothing changes visually.
For most scanned paperwork, 110 DPI at quality 60 gives a readable result at a fraction of the size. Use 150 DPI if the document has small print, and 72 DPI only when you need the smallest possible file for an upload limit. Gmail and Outlook cap attachments at 25 MB and 20 MB, and many job and government portals ask for 2 MB or less. If a text-based PDF made in Word gets bigger with strong mode, use Lossless instead, because its text was already compact.
Frequently asked questions
Is my PDF uploaded to compress it?
No. Compression runs entirely in your browser. The pages are rendered and re-encoded on your own device, and the smaller PDF is saved directly to your downloads. Your document never reaches a server.
How do I compress a PDF to under 1 MB?
Use Strong mode, set the resolution to 72 or 110 DPI and lower the quality toward 40. Check the After size, and if it is still too large, lower the settings again. Very long documents may also need to be split into parts with Split PDF.
Why can't I select text after compressing?
Strong compression converts each page into a JPEG image, so the text becomes part of the picture. If you need selectable or searchable text, links or fillable fields, use Lossless mode instead, which keeps the PDF's content unchanged.
Why did my PDF get bigger?
PDFs created from Word or similar apps store text very efficiently, so turning pages into images can increase the size. In that case use Lossless mode. If a file is already well optimized, Lossless may not shrink it much either.
Can I compress a PDF on my phone?
Yes. It works in mobile browsers, but strong compression renders every page, so long documents take longer on a phone. Lower resolutions such as 72 or 110 DPI are faster and use less memory.