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Compress PDF

Re-encodes streams and downsamples embedded images. Choose the quality you want. Your file never leaves your device.

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Compression shrinks a PDF's file size so it's easier to email or upload — by re-encoding internal streams and downsampling oversized embedded images, while letting you choose how aggressive to be.

How to compress pdf

  1. 1

    Add the PDF you want to shrink

    Drop in the file. Large, image-heavy PDFs benefit the most.

  2. 2

    Pick a quality level

    Higher quality keeps images crisp with modest savings; lower quality squeezes harder. Choose based on whether the PDF is for print or screen.

  3. 3

    Compress and download

    The tool re-encodes the file and gives you the lighter version to save.

Everything runs in your browser. Your file is never uploaded — there’s no server to send it to, no sign-up, and nothing to delete afterward.

Frequently asked questions

Why is my PDF so large in the first place?
Usually high-resolution scanned images or photos embedded at full camera resolution. Text-only PDFs are already small; image-heavy ones benefit most from compression.
Will compression make the text blurry?
No. Text and vector graphics stay sharp — only raster images are downsampled, and only to the degree you pick.
How much smaller will my file get?
It depends entirely on the content. Scanned or photo-heavy PDFs often shrink 50–80%; a PDF that's mostly text may barely change because there's little to compress.
Does the file get uploaded for compression?
No. Everything is processed in your browser, so even sensitive documents stay private.
Why does compression run in the background?
Heavy image processing happens off the main thread in a web worker, so your browser stays responsive instead of freezing on large files.

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