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Compress PDF
Make your PDF small enough to email or upload.
Processed locally — your files never leave your device
How to use Compress PDF
- 1
Open the PDF that's too big.
- 2
Pick a preset — Extreme, Recommended or Light — or dial in custom resolution and quality.
- 3
Optionally convert to grayscale for extra savings.
- 4
Click Compress and check the before/after size on the result.
About this tool
"Attachment exceeds the size limit" — the eternal email problem. Scanned PDFs are the usual culprits: a phone-scanned 20-page contract can easily weigh 40 MB because every page is a huge photograph. This tool re-renders each page at a sensible resolution and re-encodes it with efficient JPEG compression, routinely cutting scans to a fifth of their size or less.
The presets map to real uses. Light (150 DPI, high quality) is nearly indistinguishable from the original — right for documents people will read carefully. Recommended (120 DPI) is the email sweet spot. Extreme (96 DPI) prioritizes minimum size for archives and quick reference copies. Custom mode exposes the raw DPI and quality dials, and the grayscale switch drops color for another meaningful saving on scans that were never colorful to begin with.
One honest trade-off, stated plainly because most compressors hide it: this method rebuilds pages as optimized images, so selectable text in the original becomes non-selectable in the compressed copy. For scanned documents — the files that actually need compressing — nothing is lost, since scans have no real text anyway. For born-digital PDFs that are mostly text, compression gains are small and the trade-off rarely worth it; your original file is never touched either way.
Frequently asked questions
How much smaller will my file get?
Scanned and image-heavy PDFs typically shrink 60–90% on the Recommended preset. Text-only digital PDFs are already compact and may shrink little — the live before/after readout tells you exactly what happened.
Why isn't text selectable after compression?
Compression re-renders each page as an optimized image, which is how the big savings happen. If you need a compressed file with selectable text, run the result through our OCR tool to add a recognized text layer back.
Which preset should I use?
Recommended, unless you have a reason otherwise. Go Light when fine print and detail matter; go Extreme when the only goal is fitting under an upload limit.
Is there a file size limit?
No fixed limit — processing is local. Very large files (hundreds of MB) depend on your device's memory; pages are processed one at a time to keep usage in check.
Does compressing touch my original file?
Never. You get a new, smaller copy; the original stays exactly as it was on your disk.