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Compress PDF files online

Compress a PDF to a smaller file size while keeping it readable, so it fits an email attachment limit or an upload form.

Coming soon

We’re building Compress. In the meantime, try one of the related tools below.

How to compress PDF files online

  1. 1

    Open your PDF

    Select the PDF that is too large to send.

  2. 2

    Choose a level

    Light for printing, Recommended for everyday use, or Strong when the file has to be small.

  3. 3

    Download the smaller PDF

    You see the old and the new size before you save, so you can try another level.

Private by design

Your files are processed on your own device and never uploaded to a server.

Fast

No waiting for uploads or downloads. Results are ready in seconds.

Free, no signup

Use every tool without creating an account or adding a watermark.

What makes a PDF large

Text weighs almost nothing. What fills up a PDF is images: a scan at 600 dpi, or photos dropped in straight from a phone, can turn a ten-page document into 40 MB. Compressing a PDF means resampling those images to a sensible resolution and re-encoding them, which is why a scanned document can shrink by 80% or more while a text-only report barely changes — there was nothing to squeeze out of it.

Choosing a compression level

  • Light — safe for printing, a modest reduction, no visible difference.
  • Recommended — the balance most people want: much smaller, still sharp on screen.
  • Strong — for attachment limits and upload forms, where readable beats beautiful.

Common size limits

Gmail and most mail servers stop at around 25 MB per message. Government and bank upload forms are often stricter, asking for 5 MB, 2 MB or even 500 KB. If a form refuses your document, compressing it is usually quicker than scanning it again, and splitting the PDF by size is the fallback when one file simply cannot get small enough.

Frequently asked questions

How much smaller will my PDF get?

It depends on what is inside. Scans and documents full of photos often shrink by 70–90%, because the images are resampled. A text-only report may hardly change, as there was little to compress.

Will the text stay sharp?

Yes. Text and vector graphics are not resampled, so they stay crisp at every level. Compression works on the images.

What if it is still too large?

Split the document into parts under a maximum size, or remove the pages you do not need to send.

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