How to compress a PDF

Almost every oversized PDF is oversized for one reason: the images inside it are stored at far higher resolution than anything needs. Compression works by fixing that, which is why it helps enormously on some files and not at all on others.

Open Compress PDFShrink heavy files, keep the text sharp

Step by step

  1. Upload the file

    Drop your PDF onto Compress PDF. Files up to 80 MB are accepted.

  2. Choose how hard to compress

    Basic keeps the most detail. Recommended is the balanced setting most documents want. Strong produces the smallest file and is the one to pick when a size cap matters more than image fidelity.

  3. Check the saving before you keep it

    After it runs you are shown the before and after size and the percentage saved, so you can judge whether the trade was worth it. Your original is untouched either way.

Text stays sharp: only images are resampled

Text in a PDF is stored as vector instructions, not pixels, so compressing does not blur it. It prints at full sharpness at any size. What changes is the resolution of embedded photos and scans.

When compression will not help

A text-only PDF is already close to its minimum size, and compressing it can even make it slightly larger, because the file structure gets rewritten. If you see that result, keep your original. It is the better copy. Files that are large because they have hundreds of pages need Split PDF, not compression.

Common questions

How much smaller will my PDF get?

It depends entirely on what is inside. Image-heavy documents and scans routinely drop by 80–95%. Text-only documents may not shrink at all.

Will compressing make my PDF blurry?

Text will not change. Photographs and scans are resampled, so at Strong compression a heavily enlarged image will show the difference.

Is the original file changed?

No. Compression produces a new file and leaves the original on your device exactly as it was.

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