Compress a PDF

What affects PDF size

Plain PDF text usually uses little space compared with photographs stored at scanner resolution or complete font files embedded for a limited set of characters. These components determine how much reduction is available.

A text-heavy document with efficient fonts may change very little, while a PDF containing oversized scans or screenshots may have more removable image data. The result depends on the source rather than a fixed percentage.

Balanced keeps more structure

Balanced mode re-encodes embedded images and downscales them when their resolution exceeds the target use. It subsets embedded fonts to the characters used by the document when the font's licensing flags allow subsetting.

Fonts that prohibit subsetting remain embedded in full. Text stays selectable and searchable, and the result summary reports page count, the measured percentage reduction and that text was preserved.

Smaller prioritises file size

Smaller mode recompresses complete pages to pursue a lower file size. This can reduce visible detail and text sharpness because the page appearance is encoded again rather than retaining every original object.

Use Balanced first when searchable text and object structure matter. Use Smaller when a portal or message system imposes a fixed limit, then inspect small text, signatures, diagrams and photographs in the result.

The summary states that pages were recompressed. Compare the final byte size with the target limit and keep the source until the lower-quality copy has been accepted by its destination.

When compression cannot help

If the compressed candidate is not smaller than the selected PDF, the tool reports that the file is already as small as it can make it and returns the original instead of a larger copy.

Reported percentage savings are calculated from the final and source byte counts after processing. Compression runs in this browser without sending the selected PDF to a document-processing server.

Try another delivery method

A long image-heavy PDF may remain above the required limit after both modes. Further page recompression can reduce legibility without removing enough data to satisfy the destination.

Split the document when each page can travel separately, extract the pages a recipient needs or convert selected pages to images when searchable PDF structure is not required. Check the destination's accepted formats first.