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Compress PDF

To make a PDF smaller, add it, choose a level from Light to Strong, check the size saving, then download. Each page is re-rendered and its images re-encoded, which often shrinks scans and image-heavy files by 60–90%. Text in the result is no longer selectable, so use it for scans rather than text documents.

Files never leave your device

Updated

How to use Compress PDF

  1. 1Add the PDF you want to shrink.
  2. 2Choose a compression level — Light keeps the most detail, Strong makes the smallest file.
  3. 3Press Compress and wait while each page is processed.
  4. 4Compare the before and after sizes, then download if you are happy with the result.

How it works

Most of the weight in a large PDF is photographic content. Each page is rendered at a resolution matched to the level you pick, re-encoded as a JPEG at the matching quality, and written into a new document. Choosing Light keeps a high render scale and quality; Strong lowers both.

This is a raster approach, which means it is very effective on scans and image-heavy brochures — often 60–90% smaller — and much less effective on documents that are mostly text. Text-only PDFs are already tightly compressed, and rasterising them can even make the file bigger, so the tool tells you when the output is not smaller and lets you keep the original.

One trade-off is worth knowing about: because pages become images, text in the compressed file is no longer selectable or searchable. If you need to keep the text layer, use Split or Extract pages to drop the pages you do not need instead.

The file is read into your browser's memory, changed there, and handed straight back to you. Nothing is uploaded, so there is no queue and no copy sitting on a server afterwards.

Tips and common mistakes

  • Try selecting a sentence in the PDF first. If the words highlight, the file is mostly text and compression will barely help; if nothing highlights, it is a scan and will usually shrink a lot.
  • For email, aim for about 18 MB or less. Attachments grow by about a third when they are sent, so a file just under 25 MB can still be refused.
  • Delete pages nobody needs before you compress. Fewer pages means less to shrink and a smaller result.
  • Keep the original file. Compression is one-way, so send the compressed copy and keep the full-quality version.

Frequently asked questions

How much smaller will my PDF get?
Scanned documents and photo-heavy files usually drop by 60–90%. Text-only PDFs may barely change, because their text is already stored efficiently. The tool shows the exact before and after sizes before you download.
Why is my compressed file larger than the original?
That happens with text-only PDFs. Converting crisp vector text into a page image adds data rather than removing it. When this occurs the tool warns you and offers the original file instead.
Can I still select the text afterwards?
No. Compression works by turning each page into an image, so the text layer is lost. If searchable text matters, keep the original and reduce the page count instead.
Which level should I pick?
Start with Balanced. It halves most scans while keeping documents comfortably readable on screen. Use Strong for email attachments where size matters more than fine detail, and Light when the document will be printed.
Can I compress a PDF to an exact size, such as 1 MB?
There is no target-size setting. Try Balanced, then Strong, and check the size each produces. If the file is still too large, remove pages or split it into parts.
Will a compressed PDF still print well?
With Light, yes, for most documents. Strong lowers the resolution enough that small print and fine lines can look soft on paper, so keep it for documents read on screen.
Does compression keep links, form fields and bookmarks?
No. Each page is rebuilt as a picture in a new document, so interactive parts of the original do not survive. Keep the original if you need them.
Why does the text look blurry after compressing?
Compression redraws each page as an image, so text becomes pixels rather than letters. For scans that changes little. For a typed document, re-export it from the original program instead, or try the Light level.
A form rejects my PDF even though it is under the limit. Will compressing help?
Probably not. Portals also reject password-protected files, unflattened form fields, unusual file names and the wrong number of pages. Check those before compressing further.
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