Compress a PDF file
Make a PDF smaller in your browser. Lossless mode keeps text selectable and changes nothing you can see. Strong mode turns every page into a compressed picture for a much smaller file, and text stops being selectable.
How to compress a PDF file
- 1
Select or drop a PDF file.
- 2
Choose lossless compression, or strong compression and its quality.
- 3
Compress the file.
- 4
Check the measured size, then download.
What this tool does
- Lossless mode: unstored streams deflated and objects packed, nothing resampled
- Strong mode: pages redrawn as JPEG at the resolution you choose
- Measured before and after sizes, with no invented percentage
- Your original returned unchanged if no smaller file could be made
- Reads the file signature instead of trusting the file extension.
- Copies real pages. Nothing is rasterized and no page is re-rendered.
- Refuses encrypted PDFs instead of working around the protection.
- Refuses digitally signed PDFs, because saving them again would break the signature.
- Reports the measured size of the file your browser produced.
Questions about Compress PDF
- Why did my PDF not get smaller?
- Many PDFs are already compressed by the program that made them, and lossless mode cannot squeeze them further. When that happens the tool tells you and gives you your original file back, instead of a larger copy. Strong mode can still reduce it, at the cost of turning text into pictures.
- What exactly does strong compression change?
- Each page is drawn as a JPEG image and placed on a new page of the same size. The document looks the same, but text can no longer be selected, searched or copied, and links stop working. Use it for scanned documents or when size matters more than editable text.
- Will the PDF print the same?
- Lossless mode prints exactly as before. Strong mode keeps the page sizes, but print sharpness depends on the resolution you chose: 150 DPI is fine for reading, and fine print may look soft.
- Can you guarantee a target size, like under 1 MB?
- No. How small a PDF can get depends on what is inside it. The result shows the size that was actually achieved.
- Are my files uploaded to a server?
- No. This tool runs inside your browser tab, so the file bytes are read and written on your own device and are never sent to us for processing. Closing the tab discards everything, which is also why results cannot be restored after a reload.
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- Edit PDFAdd text, pictures, highlights and white-out to a PDF, or replace a line of text, right on the page.