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Size and appearance

PDF compressor

PDF compressor

Try to make a PDF smaller. The default rewrite keeps every word selectable; the picture mode saves more and gives up the text.

How this is calculated

Rewrite mode repacks the file: objects go into compressed object streams and every stream is deflated again at the highest level. No page is redrawn and no image is re-encoded. Picture mode renders each page to a JPEG at the resolution and quality you set and builds a new PDF from those pictures.

  • No compressor can promise a saving. A file that is already well packed, or one made mostly of text, often comes back the same size or slightly larger — this page reports the real figures either way and tells you to keep the original when nothing was gained.
  • Picture mode removes selectable text, hyperlinks, bookmarks and forms, and it cannot be undone. Use it for scans you only need to look at, never for a document someone must search, copy or read with a screen reader.
  • Rewrite mode removes document-level extras that the repack does not carry. Check the output before you throw away the source.
  • A PDF that already has a password cannot be opened here. Remove it first with the PDF password protector, which asks for the password you already know.
  • Your file is read by this page in your own browser. It is never uploaded, never stored on this server and never sent to anyone. Closing the tab clears it, and the download link is released as soon as you run the tool again.

Two ways to make a PDF smaller, with the honest caveat first: a file that is already well packed may come back the same size or larger, and this page tells you which happened.

Repack: the structure only

Repack mode rebuilds the container. Objects are gathered into compressed object streams, streams are deflated as tightly as the engine can manage, and the cross-reference table is rewritten. No page is redrawn, no image is re-encoded, and every word stays selectable and searchable.

This is the mode to try first, because it cannot damage what the document says. What it can do is less than people hope: a PDF exported by a modern tool is often already compressed, and repacking shaves a few per cent or nothing. Document-level extras the repack does not carry are removed, so check the output before discarding the source.

Pictures: smaller, and lossy

Raster mode renders every page to a JPEG at 72, 100 or 150 dots per inch and the quality you set, then builds a new PDF from those pictures. A 20 MB scan-heavy report can drop to a few megabytes. The price is total: text is no longer selectable or searchable, links and bookmarks disappear, and forms and signatures do not survive.

Use it for a scan that only has to be looked at, or a brochure that only has to be sent. Never for a document someone must search, copy, sign or read with a screen reader. Nothing in the output can restore the text; the original is the only copy that has it.

Questions readers ask

It came out larger. What now?

Keep the original. Both sizes are reported, and there is no sense in downloading a bigger file because it has been through a compressor.

Which resolution should I choose in picture mode?

150 dpi for something that must stay readable, 100 for a compromise, 72 when the picture is only a preview. Quality below about 60 shows blockiness around text.

Does repacking remove the metadata?

It removes document-level items that the rewrite does not carry. Check the result in the metadata viewer if a title or author must survive.

Tools

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PDF tools

Convert, join, split, number, stamp, crop, sign, fill, encrypt and inspect PDF files. Every page opens your file in this browser and writes the answer back to your own machine — nothing is uploaded.