Compress PDF

Shrink photos and scans

Shrink a PDF by recompressing the images inside it. Text and vector graphics are left untouched, so the document stays sharp where it matters.

Questions

Are my files uploaded anywhere?
No. Every tool on this site runs entirely inside your browser using JavaScript — your file is never uploaded to a server, because there is no server. You can confirm it by opening your browser’s network tab, or by disconnecting from the internet once the page has loaded: the tool still works.
Why did my PDF barely get smaller?
Because there was little to compress. Only photos and scanned pages can be recompressed — a PDF that is mostly text is already about as small as it can get, since its text is stored as instructions rather than pixels.
Will it make my document blurry?
Text and vector graphics are never touched, so they stay perfectly sharp. Photos are re-encoded at the quality level you pick, so “Smallest file” trades visible detail for size while “Best quality” is close to indistinguishable.
Which images are left alone?
Images with a transparency mask are skipped. Recompressing one without resizing its mask to match would leave the two mismatched and show as artefacts around the edges.
Can I undo it?
Not from the compressed file — the image data really is re-encoded. Your original stays untouched on your device, so keep it if you may need the full-quality version.

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