Compress PDF - Reduce PDF File Size
Shrink a PDF's file size with lossless compression, or a stronger lossy mode for scanned and image-heavy PDFs. Free, private, runs entirely in your browser.
Click to select a PDF file, or drag and drop
Your file never leaves your browserHow to Compress a PDF
- Upload the PDF you want to shrink.
- By default, Compress PDF applies lossless compression — it re-packs the file's internal structure without changing how any page looks.
- For a much bigger reduction on scanned or image-heavy PDFs, turn on Strong compression and pick an image quality, then click Compress PDF again.
- Compare the original and compressed sizes, then click Download Compressed PDF.
Example
A 12 MB scanned PDF made of high-resolution page photos often shrinks to 2-3 MB with standard compression, and much further — sometimes under 1 MB — with strong compression at a moderate quality setting, since most of its size comes from oversized images rather than text.
Common Use Cases
- Shrinking a PDF so it fits under an email attachment size limit.
- Reducing a scanned document's size before uploading it to a form or portal.
- Cutting down storage space used by large PDF archives.
FAQ
- Will standard compression change how my PDF looks? No — it's lossless. It only re-organizes the file's internal data more efficiently; every page renders identically.
- What does strong compression change? It redraws every page as a compressed JPEG image, similar to what most free online PDF compressors do for image-heavy files. This gives a much smaller file, but any selectable text becomes part of the image and can no longer be selected, searched, or copied.
- Why didn't standard compression shrink my file much? If a PDF is already efficiently packed (or mostly plain text with few images), there may be little left to compress losslessly — try strong compression if you need a smaller file and can accept the tradeoffs.
- Is my file uploaded anywhere? No — compression happens entirely in your browser; the PDF is never sent to a server.